how many numbers consisting of 1,2, or 3 digits(without repitions)can be formed using the digits 1,2,3,4,5,6?
Therefore, there are 156 numbers consisting of 1, 2, or 3 digits that can be formed using the digits 1, 2, 3, 4, 5, 6 without repetitions.
We need to find the number of numbers consisting of 1, 2, or 3 digits that can be formed using the digits 1, 2, 3, 4, 5, 6 without repetitions.
1-digit numbers: There are 6 choices for the first digit.
2-digit numbers: There are 6 choices for the first digit, and 5 choices for the second digit (since we cannot repeat the first digit).
3-digit numbers: There are 6 choices for the first digit, 5 choices for the second digit (since we cannot repeat the first digit), and 4 choices for the third digit (since we cannot repeat the first or second digit).
Therefore, the total number of numbers that can be formed is:
1-digit numbers: 6
2-digit numbers: 6 x 5 = 30
3-digit numbers: 6 x 5 x 4 = 120
The total number of numbers is the sum of these:
6 + 30 + 120 = 156
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solve the equation using the quadratic formula. 3v^2+3=-v
Answer:
v=− 1± i √35 /6
Step-by-step explanation:
Solve the equation for v by finding a , b , and c of the quadratic then applying the quadratic formula.
1. Solve for the unknown in each triangle. Round each answer to the nearest tenth.
The values of the missing sides are;
a. x = 35. 6 degrees
b. x = 15
c. x = 22. 7 ft
d. x = 31. 7 degrees
How to determine the valuesTo determine the values, we have;
a. Using the tangent identity;
tan x = 5/7
Divide the values
tan x = 0. 7143
x = 35. 6 degrees
b. Using the Pythagorean theorem
x² = 9² + 12²
find the square
x² = 225
x = 15
c. Using the sine identity
sin 29= 11/x
cross multiply the values
x = 11/0. 4848
x = 22. 7 ft
d. sin x = 3.1/5.9
sin x = 0. 5254
x = 31. 7 degrees
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in a recent semester at a local university 520 students enrolled in both general chemistry and calculus 1. Of these students 88 received an A in general chemistry 76 received an A in calculus, and 31 received an A in both general chemistry and calculus. Find the probability that a randomly chosen student received an A in general chemistry or calculus or both?
Let Ch and C denote the events of a student receiving an A in chemistry or calculus, respectively. We're given that
P(Ch) = 88/520
P(C) = 76/520
P(Ch and C) = 31/520
and we want to find P(Ch or C).
Using the inclusion/exclusion principle, we have
P(Ch or C) = P(Ch) + P(C) - P(Ch and C)
P(Ch or C) = 88/520 + 76/520 - 31/520
P(Ch or C) = 133/520
A) NO CHANGE
B) famous and well-known
C) famous and commonly known
D) famous, commonly known
The correct option is B. Famous and well-known.
A person who is widely known is said to be famous, renowned, celebrated, noteworthy, notorious, distinguished, prominent, or illustrious. Being extensively and well known, even for a little period of time, is all that being famous really means. A known actress suggests greater honor and acclaim.
Celebrated, distinguished, eminent, illustrious, notable, notorious, and renowned are some popular synonyms for famous. All of these phrases refer to being "known far and wide," while "famous" only refers to the reality of having a large and widespread following.
Disclaimer
8 famous images showed Tweed with a bag of money in place of his
A) NO CHANGE
B) famous and well-known
C) famous and commonly known
D) famous, commonly known
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In the diagram above, O is the centre of the circle with radius of 13 cm and AC = 12 cm. Find the length of SB, in cm.
Answer:
Step-by-step explanation:
\(OA = 13, AS=\frac{1}{2}AC=6\)
Then
\(OS^2=OA^2-AS^2=13^2-6^2=169-36=133.\)
Now
\(SB=OB-OS=13-\sqrt{133}\)
Please can you explain the answer:
I got
1/2n^2 +n^2 - 7/2
but it says this is wrong
Answer:
an = 1/2n² -1/2n -2
Step-by-step explanation:
You want a formula for the n-th term of the quadratic sequence -2, -1, 1, 4.
Linear equationsUsing x = 1, 2, 3 and y = -2, -1, 1 we can write equations for the coefficients a, b, c of the quadratic expression ax² +bx +c.
a(1²) +b(1) +c = -2
a(2²) +b(2) +c = -1
a(3²) +b(3) +c = 1
SolutionSubtracting the first equation from the other two, we get ...
3a +b = 1
8a +2b = 3
Subtracting twice the first from the second of these, we get ...
(8a +2b) -2(3a +b) = (3) -2(1)
2a = 1
a = 1/2
Then b can be found from ...
b = 1 -3a = 1 - 3/2 = -1/2
And c can be found from ...
-2 -b -a = c = -2 -(-1/2) -(1/2) = -2
The formula is ...
an = 1/2n² -1/2n -2
__
Additional comment
For systems of equations, the solver used in the second attachment works well. It tells us (a, b, c) = (1/2, -1/2, -2) as we found above.
Alternate solution
The first differences of the given terms are ...
1, 2, 3
And their differences are ...
1, 1
The coefficient of n² is half this second-difference value: 1/2.
If you subtract 1/2n² from the given terms, you get ...
-5/2, -3, -7/2, -4
This arithmetic sequence has the formula ...
a1 +d(n -1)
-5/2 +(-1/2)(n -1) = -1/2n -2
Adding this to the term we subtracted gives ...
an = 1/2n² -1/2n -2 . . . . . as above
Do this pls 35 points
Answer:
x = 68
Step-by-step explanation:
If you look at the triangle properly, it is a isosceles triangle where two legs are equal to each other.
The answer for x will be:
56 + 56 + x =180
112 + x = 180
x = 68
Juan has 3 blue markers and 4 red markers in his book bag. He randomly chooses 6 markers from the bag. Which event is certain
The event of Juan choosing at least one blue marker from the bag when randomly selecting 6 markers is certain.
In this scenario, Juan has a total of 7 markers in his bag, with 3 blue markers and 4 red markers. When he randomly chooses 6 markers from the bag, it is certain that he will select at least one blue marker. This is because there are more blue markers (3) than the number of markers he is selecting (6).
To understand why this event is certain, consider the worst-case scenario where Juan selects all 4 red markers first. Even in this case, there will still be 2 markers left in the bag, both of which are blue. Therefore, Juan is guaranteed to choose at least one blue marker when selecting 6 markers from the bag.
Since there are more blue markers available than the number of markers Juan is choosing, it is certain that he will select at least one blue marker. This makes the event of choosing at least one blue marker from the bag when randomly selecting 6 markers a certain event.
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Please help if possible!!
Answer:
I think 12 is B yh I hope so
Answer:
11. a
Step-by-step explanation:
-2x + 5( 3 + 2x )
-2x + 15 + 10x
8x + 15
two cyclists, 42 miles apart, start riding toward each other at the same time. one cycles 2 times as fast as the other. if they meet 2 hours later, what is the speed (in mi/h) of the faster cyclist?
The speed of the faster cyclist is 14\ miles/hr.
What is speed?
It is the average distance coverd in unit time. It is also defined as the rate of change of distance with respect to time.
Since the speed of the first cyclist is double than the second cyclist hence, the first cyclist will cover the double distance than the second cyclist. Consider the first cyclist covers 2s distance and first cyclist covers s distance. The sum of these two distances should be 42 miles. Hence,
\(2s+s=42\\3s=42\\s=14\)
Now, distance coverd by the first cyclist is \(2s=2\times 14\\=28 \ $miles\).
Now, both the cyclists meet after 2 hr hence, time taken by the first cyclist is 2 hr.
\(Speed=\frac{Total\ distance}{Total\ time}\\=28\ miles/2 \ hr\\=14\ miles/hr\)
Hence, the speed of the faster cyclist is 14\ miles/hr.
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What is the range of this function?
Answer:
\( \\b.( - 8 - 356781012)\)
9.
Write a function rule for the table.
A. f(x) = –4x
B. f(x) = 4 – x
C. f(x) = x + 4
D. f(x) = x – 4
Answer:
B. f(x) = 4 – x
Step-by-step explanation:
Answer:
b. f(x) = 4 -- X Amadodcnfnfkdi
Small scooters cost £80 and large scooters cost £130. A school buys few scooters for the playground for £1000. How many of the smaller and larger scooter did they buy?
Answer:
Small scooters = 6
Large scooters = 4
Step-by-step explanation:
Let S represents small scooter and L represents large scooter
The cost of a small scooter is £80
Mathematically, the cost of S number of small scooters is
80S
The cost of a large scooter is £130
Mathematically, the cost of L number of large scooters is
130L
The total amount spent on both scooters is £1000
Mathematically,
80S + 130L = 1000
So we have 2 unknowns and only 1 equation. Therefore, we have use trial and error method .
Trial and Error Method:
80S + 130L = 1000
80S = 1000 - 130L
S = (1000 - 130L)/80
Let’s suppose they bought 1 large scooter
S = (1000 - 130(1))/80
S = 10.875
Number of scooters cannot be in fraction so 1 doesn’t work
Let’s suppose they bought 2 large scooter s
S = (1000 - 130(2))/80
S = 9.25
Number of scooters cannot be in fraction so 2 doesn’t work
Let’s suppose they bought 3 large scooter s
S = (1000 - 130(3))/80
S = 7.625
Number of scooters cannot be in fraction so 3 doesn’t work
Let’s suppose they bought 4 large scooters
S = (1000 - 130(4))/80
S = 6
So that means they bought 6 small scooters and 4 large scooters.
Similarly, other combinations for scooters don’t work since they yield either fractional value or negative value which cannot be correct.
Therefore, the only possible combination of small and large scooters is
6 Small scooters
4 Large scooters
Verification:
80S + 130L = 1000
80(6) + 130(4) = 1000
480 + 520 = 1000
1000 = 1000 (satisfied)
The blades of a windmill turn on an axis that is 30 feet from the ground. The blades are 10 feet long and complete 2 rotations every minute. Write a sine model, y
This is the sine model, y that represents the height above the ground of one of the blades of the windmill at any given time t.
Given that the blades of a windmill turn on an axis that is 30 feet from the ground. The blades are 10 feet long and complete 2 rotations every minute. Let's find the sine model, y. Let's begin by writing the sine function where y represents the height above the ground of one of the blades of the windmill at any given time t and the constant 30 represents the height of the axis. Let's take A to be the amplitude of the function since the blades oscillate between a minimum height of 20 feet above the ground and a maximum height of 40 feet above the ground. Let's also take T to be the period of the function since the blades complete two full rotations in one minute or 2π radians in one period.T = 1 minute = 2π radians per period∴ T = 2π/1 = 2πA = (40 − 30)/2 = 5
To obtain the vertical shift, let's find the average of the minimum and maximum heights since the sine function oscillates above and below the horizontal axis:y = Asin(ωt) + b Where A is the amplitudeω is the angular frequency b is the vertical displacement of the graph
The vertical shift, b = (20 + 40)/2 = 30Since the blades are completing two full rotations in one minute, we can convert this to radians per second as shown:2 rotations = 4π radians2 rotations per minute = 4π radians per minute4π radians per minute = 4π/60 radians per secondω = 4π/60 radians per second
Substituting the values into the sine function, we obtain:y = 5sin[(4π/60)t] + 30Explanation:To summarize the given problem, the blades of a windmill turn on an axis that is 30 feet from the ground. The blades are 10 feet long and complete 2 rotations every minute. We are to write a sine model, y. From the above explanation, we have found the amplitude (A), period (T), angular frequency (ω), and vertical displacement (b) of the sine function. We then substituted these values into the general form of the sine function to obtain the specific sine model:y = 5sin[(4π/60)t] + 30
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A general arranges his students to form a perfect square.He finds that in doing so 60 soldiers were left out if total number of soldiers be 8160 find the number of soldiers in each row
Answer:
90
Step-by-step explanation:
Given that :
Number of soldiers = 8160
Number left out = 60
Result of arrangement gives a perfect square ;
Hence, the number of soldiers which makes up the arrangement will be ;
Total number of soldiers - number left out
8160 - 60 = 8100
Hence 8100 soldiers were used to form a perfect square ;
Number of soldiers in a row :
√8100 = 90
Hence, we have 90 soldiers in a row
Identify the characters of series below. nvž enn |||-) En=12 100 1-) Σπίο 3* 2"-1 ||-) En=2 n A) I Convergent, II Divergent, III Convergent B) I Convergent, Il Convergent, III Divergent C) I Convergent, II Convergent, III Convergent D) I Divergent, Il Divergent, III Divergent E) I Divergent, II Divergent, III Convergent
Based on the information, we can determine convergence or divergence of series.The given options do not provide a clear representation of potential outcomes.It is not possible to select correct option.
The given series is "nvž enn |||-) En=12 100 1-) Σπίο 3* 2"-1 ||-) En=2 n". In the series, we have the characters "nvž enn |||-)" which indicate the series notation. The characters "En=12 100 1-" suggest that there is a summation of terms starting from n = 12, with 100 as the first term and a common difference of 1. The characters "Σπίο 3* 2"-1 ||-) En=2 n" indicate another summation, starting from n = 2, with a pattern involving the operation of multiplying the previous term by 3 and subtracting 1.
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Please help 60 points for a rapid answer-In the figure below which of the following is true in circle E?
Answer:
all 3 options are true : A, B, C
Step-by-step explanation:
warning : it has come to my attention that some testing systems have an incorrect answer stored as right answer for this problem.
they say that A and C are correct.
but I am going to show you that if A and C are correct, then also B must be correct.
therefore, my given answer above is the actual correct answer (no matter what the test systems say).
originally the information about the alignment of the point F in relation to point E was missing.
therefore, I considered both options :
1. F is on the same vertical line as E.
2. F is not on the same vertical line as E.
because of optical reasons (and the - incomplete - expected correct answers of A and C confirm that) I used the 1. assumption for the provided answer :
the vertical line of EF is like a mirror between the left and the right half of the picture.
A is mirrored across the vertical line resulting in B. and vice versa.
the same for C and D.
this leads to the effect that all 3 given congruence relationships are true.
if we consider assumption 2, none of the 3 answer options could be true.
but if the assumptions are true, then all 3 options have to be true.
now, for the "why" :
remember what congruence means :
both shapes, after turning and rotating, can be laid on top of each other, and nothing "sticks out", they are covering each other perfectly.
for that to be possible, both shapes must have the same basic structure (like number of sides and vertices), both shapes must have the same side lengths and also equally sized angles.
so, when EF is a mirror, then each side is an exact copy of the other, just left/right being turned.
therefore, yes absolutely, CAD is congruent with CBD. and ACB is congruent to ADB.
but do you notice something ?
both mentioned triangles on the left side contain the side AC, and both triangles in the right side contain the side BD.
now, if the triangles are congruent, that means that each of the 3 sides must have an equally long corresponding side in the other triangle.
therefore, AC must be equal to BD.
and that means that AC is congruent to BD.
because lines have no other congruent criteria - only the lengths must be identical.
A teacher recorded unit 4 test scores from her class.
58, 64, 66, 70, 71, 75, 77, 80,
84, 85, 87, 90, 93, 95, 96.
Find the percentile rank of a score of 71 on this street -
Victor is in the 60th percentile, what was his score?
The percentile score of 71 on test score is 27 and the score of victor is 71.
What is Statistics?Statistics is the science concerned with developing and studying methods for collecting, analyzing, interpreting and presenting empirical data.
Given, the teacher recorded unit 4 test scores from class.
The scores are: 5,4,66,70,71,75,77,80,84,85,87,90,93,95 and 96.
A percentile is a value on a scale of one hundred that indicates the percent of a distribution that is equal to or below it.
The percentile rank of a score of 71 on the test is find by formula
\(R_{100} =\frac{100(N < )+\frac{1}{2} }{N}\)
=100×4+1/2(1)/15
=400+0.5/15
=400.5/15
=26.7=27th
Now we need to find the score of victor who has 60th percentile.
60=Score/15
score=71
Hence, the percentile score of 71 on this test score is 27 and the score of victor is 71.
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How do you expand and simplify a binomial?
In order to expand and simplify an expression, we need to multiply out the brackets and then simplify the resulting expression by collecting the like terms. Expanding brackets is the process by which we remove brackets. It is the reverse process of factorization.
To expand and simplify a binomial, use the distributive property. The distributive property states that for any two binomials, the product of each term in the first binomial and each term in the second binomial should be added together to get the expanded form of the expression.
For example, the binomial (2x + 3)(4x + 7) can be expanded using the distributive property by multiplying each term of the first binomial with each term in the second binomial. This gives us:
(2x × 4x) + (2x × 7) + (3 × 4x) + (3 × 7)
And simplifying this expression yields 8x² + 14x + 21.
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15 more than ten times a number equals 60. What is the number?
Answer:
4.5
Step-by-step explanation:
Let the number be x, then:
10x + 15 = 6010x = 60 - 1510x = 45x = 45/10x = 4.5The number is 4.5
Answer:
4.5
Step-by-step explanation:
let the number be x , then
10x + 15 = 60 ( subtract 15 from both sides )
10x = 45 ( divide both sides by 10 )
x = 4.5
The number is 4.5
a math teacher claimed that the average grade of the students in her algebra 2 classes this year would be equal to the average grade of the same students in algebra 1 classes two years ago. the average grade of algebra 1 students two years ago was 92%. in a random sample of 25 current algebra 2 students, the average grade was 87%, with a standard deviation of 7%. is there enough evidence to reject the teacher's claim?
From the hypothesis test conducted, the calculated t-statistic of -3.57 is less than the lower critical t-value of -2.064. This tells us that the observed sample mean of 87% is significantly different from the claimed population mean of 92% at the 0.05 significance level. Therefore, the null hypothesis can be rejected and conclusions can be made that that there is enough evidence to suggest that the average grade of the students in the Algebra 2 class this year is not equal to the average grade of the same students in the Algebra 1 class two years ago.
How do we conduct a hypothesis test?To determine whether there is enough evidence to reject the teacher's claim, we can conduct a hypothesis test. A one-sample t-test will be us to compare sample mean.
Here are the sample statistics:
Sample size (n) = 25
Sample mean (X) = 87%
Sample standard deviation (s) = 7%
A significance level (α) of 0.05, wil be used
We first calculate the t-statistic, with (X - μ) / (s/√n),
t = (87 - 92) / (7/√25) = -5 / (7/5) = -3.57
Then, we check this value against the critical t-value for a two-tailed test with 24 degrees of freedom (n-1), and α = 0.05.
The critical t-values for a two-tailed test at α = 0.05 and df = 24 are approximately -2.064 and +2.064.
-3.57 t-test is less than the lower critical t-value of -2.064. This means that the observed sample mean of 87% is significantly different from the claimed population mean of 92% at the 0.05 significance level.
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For which two functions does f(x)→+∞ as x→+∞?
Explain your reasoning.
f(x)=14x+3
g(x)=−35x−8
h(x)=2x−1
What is the anwser to this? Explain in detail please.
-12(-12+x)<12
The solution to the inequality expression is x > 11
Inequality expressionGiven the inequality expression
-12(-12+x)<12
Expand
144 - 12x < 12
Subtract 144 from both sides
-12x < 12 - 144
-12x < -132
Divide both sides by -12
-12x/-12 > -132/-12
x > 11
Hence the solution to the inequality expression is x > 11
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Saumya read one third of book on Monday, two fifth of the remaining book on Tuesday, and still 60 pages were left to read. Find the total number of pages she read on Monday and Tuesday.(1) 90(2) 50(3) 40(4) 60
Fraction : Word problems may involve fractions if we are dealing with partial values coming from a whole.
Total number of pages she read on Monday are 50 pages .
Total number of pages she read on Tuesday are 40 pages .
Operations with Fractions:
we have to remeber some important rules, making fractions similar for addition and subtraction, and applying the reciprocal for the divisor in division. The operations would depend on the analysis of the problem.
We have given in the problem that on Monday, Saumya read 1/3 of a book and on Tuesday, she read 2/5 of the remaining pages. After those, the remaining number of pages is 60
Firstly, we have to find the total number of pages the book has.
We will begin by finding the remaining fraction of pages after Saumya read on Monday. We will subtract 1/3 from 1 whole since she read from the beginning of the book.
1 − 1/3 = 2/3
Now, we know that on Tuesday, Saumya began reading with 2/3 remaining in the book. We will now find the fraction of the pages Saumya read on Tuesday. We know that it's 2/5 of the remaining pages, so it's 2/5 of 2/3
=> 2/5× 2/3 = 4/15 of the total number of pages of the book on Tuesday. So now, we will find the total fraction of the number of pages of the book that Samuya has read so far. This is so we can compare this fraction with the number of pages remaining. For this, we will add
1/3 + 4/15 = (5 + 4)/15 = 9/15
then 1 - 9/15 = (15-9)/15 = 6/15
This means that there would be another 6/15
= 2/5 of the book remaining and
that the remaining 2/5 of the book = 60 pages the total number of pages = 60/2/5
= 60×5/2 = 150
Therefore, the book has a total of 150 pages.
Total number of pages she read on Monday
= 1/3 of 150 = 50 pages
Total number of pages she read on Tuesday
= 4/15 of 150 = 40 pages
Hence, the total number of pages she read on Monday and Tuesday are 50 pages and 40 pages respectively.
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Determine which of the following sets are countable. )
A) B = {b € R: 2
B) C = {c ER: 2
C) N×{1} = {(n, 1) : n € N }
D) Rx R = {(x, y): x, y € R}
These are the countable and uncountable a) The set of negative rationals (p) is countable. b) The set {r + √(2n) : r ∈ ℚ, n ∈ ℕ} is uncountable. c) The set {x ∈ ℝ : x is a solution to ax² + bx + c = 0 for some a, b, c ∈ ℚ} is countable.
a) The set of negative rationals (p) is countable. To see this, we can establish a one-to-one correspondence between the negative rationals and the set of negative integers. We can assign each negative rational number p to the negative integer -n, where p = -n/m for some positive integer m.
Since the negative integers are countable and each negative rational number has a unique corresponding negative integer, the set of negative rational is countable.
b) The set {r + √(2n) : r ∈ ℚ, n ∈ ℕ} is uncountable. This set consists of numbers obtained by adding a rational number r to the square root of an even natural number multiplied by √2. The set of rational numbers ℚ is countable, but the set of real numbers ℝ is uncountable. By adding the irrational number √2 to each element of ℚ,
we obtain an uncountable set. Therefore, the given set is also uncountable.
c) The set {x ∈ ℝ : x is a solution to ax² + bx + c = 0 for some a, b, c ∈ ℚ} is countable. For each quadratic equation with coefficients a, b, c ∈ ℚ, the number of solutions is either zero, one, or two. The set of quadratic equations with rational coefficients is countable since the set of rationals ℚ is countable.
Since each equation can have at most two solutions, the set of solutions to all quadratic equations with rational coefficients is countable as well.
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Triangle A is the pre-image, and triangle B is the image. Find the scale factor for this dilation if the center of dilation is at (0,0)
Answer:
The scale factor is 3
Step-by-step explanation:
6/2=3 (one of the triangles sides)
can someone help me, please?
Answer:
None of them are correct maybe?
Step-by-step explanation:
Because the length of bd is 56 and AE is would be bigger but it is not double the size of it so it would be none of these are correct.
I’m jacks class, 18 of the students are tall and 10 are short. In Michael’s class 54 students are tall and 30 short which class has a higher ratio of tall to short students.
Answer:
neither they are the same value of ratio
Step-by-step explanation:
18:10 - jacks class
54:30- micheal’s class
18:10
x3 x3
54:30
Meaning the ratio is the exact same value
Hopes this helps please mark brainliest
plz solve it is ergent
Answer:
first term = 2 ...(given)
second term = f (2) = f (2-1) * 5 = 1 * 5 = 5. .....[according to the formula f(n) = f (n -1) *5 ]
third term = f (3) = f ( 3 - 1 ) * 5 = 2 * 5 = 10
fourth term = f (4) = f (4 - 1) * 5 = 3 * 5.= 15
fivth term = f (5) = f ( 5 - 1) * 5 = 4* 5. =20