Answer:
f(-2) is 14.
Step-by-step explanation:
We have been given the function:
We have to find f(-2)
That means put x= -2 in the given function we get:
After simplification we will get:
After further simplification we will get the required result:
Hence, ƒ (-2) is 14
K-12. Grade 7th.
Multiply.
(−1217)⋅(−16)
What is the product?
Enter your answer as a simplified fraction in the box.
Use the points A(1,5), B(1,-4), C(-3,5), D(-3,-4)
Pls lmk by Thursday
Using the points A(1,5), B(1,-4), C(-3,5), D(-3,-4) the following are matched:
Distance between points B and C = √97.
Distance between points A and B = 9.
Midpoint between points B and C = (-1, 1/2).
Midpoint between C and D = (-3, 1/2).
Slope of the line through B and D = 0.
What is the distance between two points of a line?The distance between two points of a line is given as:
Distance = \(\sqrt{c - a)^2 + (d - b)^2}\)
We have,
A(1,5), B(1,-4), C(-3,5) and D(-3,-4).
The distance between A and B.
= \(\sqrt{(1 - 1)^2 + (-4 - 5)^2}\)
= √81
= 9
The distance between B and C.
= \(\sqrt{(-3 - 1)^2 + (5 + 4)^2}\)
= √(16 + 81)
= √97
The midpoint (x, y) between B and C.
x = (1 - 3)/2 = -1
y = (-4 + 5) / 2 = 1/2
The midpoint (x, y) between C and D.
x = (-3 -3) / 2 = -6/2 = -3
y = (5 - 4) / 2 = 1/2
The slope of the line through points B and D.
= (-4 + 4) / (-3 - 1)
= 0/ -4
= 0
Thus,
The distance between A and B is 9.
The distance between B and C is √97.
The midpoint between B and C is (-1, 1/2).
The midpoint between C and D is (-3, 1/2).
The slope of the line through B and D is 0.
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Can you solve the problems
Derek has 4 shirts, 7 pairs of pants, and 3 blazers. How many possible outfits can he make?
What is the slope of the line perpendicular to 2x-3y=8
Answer:
y = - \(\frac{3}{2}\)x - \(\frac{8}{3}\)
Step-by-step explanation:
2x-3y=8
rewrite, solve for y
3y = 2x - 8
divide by 3
y = \(\frac{2}{3}\)x - \(\frac{8}{3}\)
perpendicular = negative reciprocal slope = - \(\frac{3}{2}\)
Armando and Mikayla have a new grandson. How much money should they invest now so that he
will have $80,000 for his college education in 18 years? The money is invested at 8% compounded
annually
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Answer:
$20,020
Step-by-step explanation:
The future value formula is helpful.
FV = P(1 +r)^t
$80,000 = P(1.08^18) = 3.9960195P
P = $80,000/3.9960195 = $20,019.92
They should invest about $20,020 now.
Three forces, (15i+j) N, 5qi – pj) N and (-3pi - gj) N, where p and q are
constants, act on a particle.
Given that the particle is in equilibrium, find the value of p and the value of q.
Given that the particle is in equilibrium, the value of p = 2.5 and the value of q = -1.5
To answer the question, we need to know what force are
What is a force?A force that thing which cause a change in motion of an object
Since there are three forces (15i + j) N, (5qi – pj) N and (-3pi - qj) N, where p and q are constants, act on a particle. Given that the particle is in equilibrium, the resultant force on the particle is zero.
What is a resultant force?A resultant force is a vector sum of two or more forces
So, (15i + j) N + (5qi – pj) N + (-3pi - qj) N = 0i + 0j
15i + 5qi - 3pi + j - pj - qj = 0i + 0j
(15 + 5q - 3p)i + (1 - p - q)j = 0i + 0j
Equating components, we have
15 + 5q - 3p = 0 and 1 - p - q = 0
5q - 3p = -15 (1) and - p - q = -1
5q - 3p = -15 (1) and p + q = 1 (2)
From equation (2), p = 1 - q (3).
The value of q
Substituting p into (1), we have
5q - 3p = -15 (1)
5q - 3(1 - q) = -15
5q - 3 + 3q = -15
5q + 3q = -15 + 3
8q = -12
q = -12/8
q = -3/2
q = - 1.5
The value of p
Substituing q into (3), we have
p = 1 - q
p = 1 - (-3/2)
p = 1 + 3/2
p = (2 + 3)/2
p = 5/2
p = 2.5
So, the value of p = 2.5 and the value of q = -1.5
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Question 5
Find the value of x.
(3x - 14) (2x + 10)°
3x - 14 here, 2x + 10 here. Consequently, X has a value of 14. In algebra, the letter "x" is frequently used to denote a value that is still unknown. It is referred to as a "variable" or "unknown" at times.
How to find the variable X ?In algebra, the letter "x" is frequently used to denote a value that is still unknown. The term "variable" or "unknown" is used to describe it. x in x+2=7 is a variable. Not only can a variable be "y," "w," or any other letter, name, or symbol, it can also be "x." Examine: Variable
Bring the variable to one side of the equation, and then move all the other values to the other side by performing arithmetic operations on both sides of the equation to find the value of x. To determine the answer, simplify the values.
An experiment's independent variable is a variable that stands in for a variable that is being altered. In equations, the independent variable is frequently denoted by the variable x. X is the variable here.
\($$3 x-14-(2 x)=0$$\\\)
We shift every term to the left:
\($3 x-14-(2 x)=0$\)
We combine all the numbers and all the variables.
\($$x-14=0$$\)
All terms containing x are shifted to the left, and all other terms are shifted to the right.
\($$x=14$$\)
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As the CAPS document outlines, the Content Specification and Content Clarification for Patterns, Functions, and Algebra shows sequenced mathematics content topics and a content area spread. In the Intermediate Phase, select one topic and report on the topic sequence and content area spread. Your report should demonstrate mathematics concepts and procedures’ hierarchical and logical progression.
Answer:
Step-by-step explanation:
In the Intermediate Phase of mathematics education, one topic that demonstrates a hierarchical and logical progression in patterns, functions, and algebra is the concept of "Linear Equations."
The topic of Linear Equations in the Intermediate Phase builds upon the foundation laid in earlier grades and serves as a stepping stone towards more advanced algebraic concepts. Here is an overview of the topic sequence and content area spread for Linear Equations:
Introduction to Variables and Expressions:
Students are introduced to the concept of variables and expressions, learning to represent unknown quantities using letters or symbols. They understand the difference between constants and variables and learn to evaluate expressions.
Solving One-Step Equations:
Students learn how to solve simple one-step equations involving addition, subtraction, multiplication, and division. They develop the skills to isolate the variable and find its value.
Solving Two-Step Equations:
Building upon the previous knowledge, students progress to solving two-step equations. They learn to perform multiple operations to isolate the variable and find its value.
Writing and Graphing Linear Equations:
Students explore the relationship between variables and learn to write linear equations in slope-intercept form (y = mx + b). They understand the meaning of slope and y-intercept and how they relate to the graph of a line.
Systems of Linear Equations:
Students are introduced to the concept of systems of linear equations, where multiple equations are solved simultaneously. They learn various methods such as substitution, elimination, and graphing to find the solution to the system.
Word Problems and Applications:
Students apply their understanding of linear equations to solve real-life word problems and situations. They learn to translate verbal descriptions into algebraic equations and solve them to find the unknown quantities.
The content area spread for Linear Equations includes concepts such as variables, expressions, equations, operations, graphing, slope, y-intercept, systems, and real-world applications. The progression from simple one-step equations to more complex systems of equations reflects a logical sequence that builds upon prior knowledge and skills.
By following this hierarchical progression, students develop a solid foundation in algebraic thinking and problem-solving skills. They learn to apply mathematical concepts and procedures in a systematic and logical manner, paving the way for further exploration of patterns, functions, and advanced algebraic topics in later phases of mathematics education.
3. Function G is defined by the equation G(x) = [x].
Function R is defined by the equation R(x) = x/+2.
Describe how the graph of function R relates to the graph of G, or sketch the graphs
of the two functions to show their relationship.
Answer: The function G(x) = [x] returns the greatest integer less than or equal to x. This means that for any value of x, G(x) will be the largest integer that is less than or equal to x. For example, G(3.5) = 3 and G(5) = 5.
The function R(x) = x/+2, x is any real number, this function returns the value of x incremented by 2. In other words, it is the result of adding 2 to x.
On the other hand, the graph of R(x) is a line that goes through the point (0, 2) and has a slope of 1, this means that for every change of 1 unit in the x-axis, the y-axis will change by 1 unit as well.
When we compare the two graphs, we can see that the graph of R(x) is shifted up 2 units from the graph of G(x) . If the graph of G(x) is thought of as the "ground", the graph of R(x) is "floating" two units above it. Also, the graph of R(x) is continuous while the graph of G(x) is not.
To sum up:
-The graph of G(x) is a step function, which start at the negative infinity and jumps up to the next integer at every point.
The graph of R(x) is a line that goes through the point (0, 2) and has a slope of 1
-R(x) is always two units above G(x) , and is a continuous function, while G(x) is not.
Step-by-step explanation:
Much concern has been expressed regarding the practice of using nitrates as meat preservatives. In one study involving possible effects of these chemicals, bacteria cultures were grown in a medium containing nitrates. The rate of up take of radio-labeled amino acid (in dpm, disintegrations per minute) was then determined for each culture, yielding the following observations:
7251 6871 9632 6866 9094 5849 8957 7978 7064 7494 7883 8178 7523 8724 7468
Suppose that it is know that the mean rate of uptake for cultures without nitrates is 8000. Do the data suggest that the addition of nitrates results in a decrease in the mean rate of uptake? Test the appropriate hypotheses using a significance level of .10.
Please use all 9 steps to answer this question with exact numbers in the question. Thank you!!
1. Describe the population characteristic about which hypotheses are to be tested.
2. State the null hypothesis H0.
3. State the alternative hypothesis Ha.
4. Choose the significance level, a, for the test. Note: Many times a will be specified in the problem, so just state it here. If it is not given, you are free to choose an appropriate significance level like a = .05
5. Check to make sure that any conditions/assumptions required for the test are reasonable. Note: Even if you believe that the assumptions have not been met, make a note of that and then say, "but we will proceed with the test anyway".
6. Clearly display the test statistic to be used and calculate the observed value of the test statistic.
7. Determine the P-value associated with the observed value of the test statistic.
8. State the conclusion (reject H0 or fail to reject H0) with reference to the level of significance.
9. State a final conclusion in the context of the problem.
Answer:
1) μ = 8000
2) H0: μ ≥8000
3) Ha: μ < 8000
4) α= 0.10
5) If the sample size is at least 15 a student's t test can be used.And we assume that the variances of the two independent groups are almost equal.
6) t= x`- μ/ s.d/ √n = -0.816
7) The P- value = 0.214083.
8) The critical region is [-∞, -1.345]
9) Fail to Reject the Null Hypothesis
Step-by-step explanation:
1) The population characteristic is the population mean =μ = 8000
2) The claim is that the addition of nitrates results in a decrease in the mean rate of uptake i.e μ < 8000
The null hypothesis is that μ ≥ 8000
2) Null hypothesis: H0: μ ≥8000
3) Alternative hypothesis: Ha: μ < 8000
4) The significance level alpha = α= 0.10
5) If the sample size is at least 15 a student's t test can be used.And we assume that the variances of the two independent groups are almost equal.
Calculating mean and standard deviation using a calculator
Sample Size, n: 15
Mean= ∑ x/n = x`=: 7788.8
∑ x/n= 116832/15
St Dev, s.d(n-1) : 1002.4307
6) Test Statistic: student's t Test with d.f = n-1 = 14
t= x`- μ/ s.d/ √n
t= 7788.8-8000/1002.4307/√15
t= -0.816
7) The P- value for the observed t value is 0.214083.
The result is not significant at p < 0.10. H0 is accepted.
8) The Critical value for one sided t test at α =0.1 with 14 d.f is less than t= -1.3406
Hence the critical region is [-∞, -1.345]
Since the calculated t -0.816 value does not fall in the critical region [-∞, -1.345] there is not sufficient evidence to reject H0
9) Fail to Reject the Null Hypothesis
Sample does not provide enough evidence to support the null hypothesis and conclude that the data suggest that the addition of nitrates do not result in a decrease in the mean rate of uptake. The claim is rejected.
The population of a city was 10,000 in 2010. The population increase at an annual rate of 2.5% per year. Is the growth model function that represents the population of the city linear?
Answer:
The growth model that represents the population of this city is not linear--it is exponential:
\(f(t) = 10000( {1.025}^{t} )\)
\(t = 0 \: represents \: 2010\)
Why is x+2=0 a one step equation
Answer: answer is step by step
Step-by-step explanation:
A one-step equation is an algebraic equation you can solve in only one step. Once you've solved it, you've found the value of the variable that makes the equation true.
Hello there! I hope my answer will help you!
Look:
x+2=0
x=0-2
x=-2
Actually, it's Mental Math! :)
\(GraceRosalia\)
What is wrong with the following proof? Clearly we know that 1 does not equal 2. What rule of algebra did we break that makes this conclusion invalid? I've numbered the lines for you so you can refer to the line numbers in your explanation
An attempt to divide by zero gives a contradictory result
A rule of algebra broken is dividing by zero (leading to a contradiction) and stating a finite result
Reason:
The given calculation is presented as follows;
1. a > 0, b > 0 given
2. a = b given
3. a·b = b²
4. a·b - a² = b² - a²
5. a·(b - a) = (b + a)·(b - a)
6. a = b + a
7. 0 = b
8. b = 2·b
9. 1 = 2
From line 4, the result are;
4. a·b - a² = b² - a² = 0
5. a·(b - a) = (b + a)·(b - a) = 0
On line 6, both sides where divided by (b - a) = 0, which should given an infinite result
Therefore, one rule of algebra broken is dividing by zero to get a finite result
In line 7, we have;
7. 0 = b
From 6. a = b + a, and a = b, we have;
8. b = 2·b
Therefore, line 9 should be;
9. 0 = 2·0; 0 = 0, given that we have;
1 × 0 = 0
2 × 0 = 0
∴ 1 × 0 = 2 × 0
However
1 ≠ 2In line 9., by dividing by b = 0, again, we have;
9. 1 = 2 (a contradiction)Therefore, one rule of algebra that is broken is dividing by zero and having a finite result
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An AP is given by k,2k/3,k/3,0 .....Find the sixth term. find the nth term. If the 20th term is equal to 15, find k
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Answer:
6th term: 8k/3n-th term: an = k + (k/3)(n -1)k = 45/22 for 20th term = 15Step-by-step explanation:
You know the general term of an AP is ...
an = a1 +d(n-1)
Here, a1 = k. The common difference is ...
2k/3 -k = -k/3
So, the general term is ...
an = k +(k/3)(n -1) . . . . the general term
__
The 6th term is then ...
a6 = k + (k/3)(6 -1) = (3k +5k)/3 = 8k/3 . . . . 6th term
__
The 20th term is ...
a20 = k + (k/3)(20 -1) = 22k/3
If this is 15, then the value of k is ...
22k/3 = 15
22k = 45
k = 45/22 . . . . value of k for a20 = 15
How do you multiply 6 by 67 by 123 by 6789
Answer:
1,00,900,987 would be the answer
HELPPPP PLEASSSSEEEiffgxhxgxgkxgjxgxutx
Flight 4581 travels daily from Pittsburgh to San Antonio. The flight is due into San Antonio at 5:07 p.m. The following list gives the Flight 4581 arrival time relative to 5:07 p.m. (in minutes) for a selection of 9 days. (A negative number means that the flight arrived early.) 21, 39, 37, 25, 6,-6, -4, 40, 37 Send data to Excel
(a) What is the mean of this data set? If your answer is not an integer, round your answer to one decimal place. an integer, round your answer to one decimal place.
zero modes
(b) How man ndicate the number of mo vasluers) of the mode modes does the data set have, and what are eir values?
Question:
Flight 4581 travels daily from Pittsburgh to San Antonio. The flight is due into San Antonio at 5:07 p.m. The following list gives the Flight 4581 arrival time relative to 5:07 p.m. (in minutes) for a selection of 9 days. (A negative number means that the flight arrived early.) 21, 39, 37, 25, 6,-6, -4, 40, 37 Send data to Excel
(a) What is the mean of this data set? If your answer is not an integer, round your answer to one decimal place. an integer, round your answer to one decimal place.
b) How many modes does the data set have? and what are their values
Answer:
a) 21.2
b) Value of mode = 37
It contains just one mode
Step-by-step explanation:
Given:
x = 21, 39, 37, 25, 6,-6, -4, 40, 37
n = 9
a) Find the mean
Mean is the average value of a dataset.
Mean = Σx/n
Mean = \( \frac{21+39+37+25+6+(-6)+(-4)+40+37}{n} \)
\( = \frac{195}{9} \)
\( = 21.667 \)
The question says one decimal place.
Therefore, mean = 21.7
b) The mode of a dataset is the value that appears most frequently.
We have the following datasets:
21, 39, 37, 25, 6,-6, -4, 40, 37
The value that appears most frequently here is 37.
37 appeared twice while the rest appeared just once.
Therefore the dataset contains just one mode
Find the square root of 9 by long division method
The square root of 9 by long division method will give an answer of 3.
Steps in finding the square root1: Group the digits of 9 into pairs from right to left. Since 9 is a single-digit number, we can consider it as a pair by itself.
2: Find the largest number whose square is less than or equal to the leftmost pair. In this case, the largest number whose square is less than or equal to 9 is 3.
3: Write 3 as the divisor on the left, and the quotient on the top right.
3 √ 9 | 0
4: Multiply the divisor (3) by the quotient (3), and write the result under the 9.
3 √ 9 | 0
- 9
5: Subtract the result (9) from the leftmost pair (9), and write the difference (0) below the line.
3 √ 9 | 0
- 9
0
6: Bring down the next pair (0) to the right of the difference.
3 √ 9 | 0
- 9
0
-----
7: Double the quotient (3) and write a blank space to the right.
3 √ 9 | 0
- 9
0
-----
0
?
8: Find a digit to fill in the blank space, such that when the new divisor (37) is multiplied by the digit, the result is less than or equal to the current dividend (0). In this case, the largest digit we can use is 0.
9: Write the digit (0) as the new quotient, and write the product of the new divisor (37) and the new quotient (0) below the line.
3 √ 9 | 0
- 9
0
-----
0
0
10: Subtract the product (0) from the current dividend (0), and write the difference (0) below the line.
3 √ 9 | 0
- 9
0
-----
0
0
- 0
11: Since there are no more pairs to bring down, we have reached the end of the division. The square root of 9 is 3.
√9 = 3.
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Find the volume of the sphere. Round your answer to the nearest tenth.
Answer:
17157.28
Step-by-step explanation:
If we know that the volume of a sphere is equal to V=4/3πr3, then we can assume this.
The radius of the sphere is 16, so 16 cubed is 4096. 4096 x pi is 12867.96
12867.96 x 4/3 is 17157.28
What is the height of a solid cylinder with a mass of 26.05 g, a diameter of 3.56 cm, and a density of 2.72 g/cm^3?
Answer:
h = 0.962 cm
Step-by-step explanation:
Given that,
Mass of a solid cylinder, m = 26.05 g
The diameter of a cylinder, D = 3.56 cm
Radius, r = 1.78 cm
The density of a cylinder is 2.72 g/cm³
We need to find the height of the cylinder. Let it is h. We know that mass per unit volume is equal to density of an object. It can be given by :
\(d=\dfrac{m}{V}\\\\d=\dfrac{m}{\pi r^2 h}\\\\h=\dfrac{26.05}{\pi \times (1.78)^2\times 2.72}\\\\h=0.962\ cm\)
So, the height of the cylinder is 0.962 cm.
? points
Simplify completely :
5x - 20
9x - 36
Answer:
5/9
Step-by-step explanation:
16. A pair of equations to determine value of 2 variables
is called
Answer:
I think you're looking for the term linear equation in 2 variables
Susan invests 2 times as much money at 6 % as she does at 5 %. If her total interest after 1 year is $510, howmuch does she have invested at each rate?Susan invests $___at 5% and $___ at 6%.
The interest formula is :
\(I=Prt\)where I = interest
P = Principal amount
r = interest rate
t = time in years
From the problem, Susan invested twice the amount at 6% as she does at 5%.
If she invested P to 5%, the amount she invested to 6% will be 2P
Using the formula to calculate the two interests.
For 5% :
\(\begin{gathered} I=P(0.05)(1) \\ I=0.05P \end{gathered}\)For 6% :
\(\begin{gathered} I=2P(0.06)(1) \\ I=0.12P \end{gathered}\)The sum of the interests is $510
This will be :
\(\begin{gathered} 0.05P+0.12P=510 \\ \text{Solve for P :} \\ 0.17P=510 \\ P=\frac{510}{0.17}=3000 \end{gathered}\)She invested $3000 for 5% and $6000 for 6%
The answers are :
5% : $3000
6% : $6000
which choice is equivalent to the product below? √27·√6
So, by taking the perfect square, option D is accurate and √27·√6 is equal to either 3·√18 0r 9√2.
what is square root ?The square root of a number in mathematics is a quantity that, when multiplied by itself, yields the initial number. It is also known as a radical and is denoted by the sign "". For instance, since 3 times 3 = 9, the square root of 9 is 3. The symbol for the square root function is: √x = y, which states that y is equal to x squared. The phrase "the square base of x" should be read as "x". Since the sum of two negative integers is positive, the square root can either be positive or negative. However, the square root is typically only considered to have positive values,
given
Using the square root property, which states that the square root of a product is equivalent to the product of the square roots, we can simplify the product √27·√6 :
√27·√6 = √(27·6)
Now that we have factored out any perfect squares, we can simplify the equation under the radical sign. Since 3 has no perfect square factors and 27 can be factored as 9 3, we can write:
√(27·6) = √(9·3·6)
Taking the perfect square 9 out of this equation will further simplify it:
√(9·3·6) = √9 · √(3·6) = 3 · √18
So, by taking the perfect square, option D is accurate and √27·√6 is equal to either 3·√18 0r 9√2.
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Use all the six numerals 4, 5, 6, 7, 8 and 9 to form two 3-digit even numbers whose sum is smallest, and what is the sum?
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Answer:
476 +598 = 1074
Step-by-step explanation:
In order for the sum to be smallest, the two most-significant digits must be the smallest possible. That is, they must be 4 and 5.
The two least-significant digits must be even. The remaining even digits are 6 and 8. Then the tens digits are the digits left over: 7 and 9.
Possible sums are ...
476 +598 = 1074
478 +596 = 1074
496 +578 = 1074
498 +576 = 1074
The sum is 1074.
Add
3 2/7 + 7 5/14 as fractions
Answer:
Step-by-step explanation:
There are two methods of doing this
one is in the pin and another:
3 2/7 =23/7
7 5/14= 103/14
23/7 + 103/14 = Lcm 14
23/7 *2= 46/14
46/14 + 103/14 =149/14
149/14 = 10 9/14
what are the 6 steps to designing a statistical study
Answer:
Step 1: Write your hypotheses and plan your research design
Step 2: Collect data from a sample
Step 3: Summarize your data with descriptive statistics
Step 4: Test hypotheses or make estimates with inferential statistics
Step 5: Interpret your results
Step-by-step explanation:
What should you substitute for x in the second equation (bottom equation) in order to solve the system by the substitution method?
We substitute -1+1/6y for x in the second equation (bottom equation) in order to solve the system by the substitution method.
The given system of equations are 2x-1/3y = -2...(1)
3x+y=1...(2)
We solve this system of equations by using substitution method.
Let us solve for x in equation to substitute it in equation (2).
2x=-2+1/3y
Divide both sides of equation by 2.
x=-1+1/6y
Now plug in the value of x in equation 2.
Hence, we substitute -1+1/6y for x in the second equation (bottom equation) in order to solve the system by the substitution method.
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Peter had 208 Canadian stamps and 186 Mexican stamps for sale. The stamps were mixed up and sold in packets of 6. How many packets of stamps were there? How many stamps were left over?
Answer:
65 packets and 4 stamps
Step-by-step explanation:
The first thing we see is that the stamps are mixed... which means they must be added.
208 + 186 = 394 stamps total
Now we see that each packet has 6 stamps. So we divide the number of stamps in total by 6.
394/6= 65.66667
Now we see from that number that the stamps can't quite make 66 packets, so there are 65 packets.
Now we find the number of stamps left over by multiplying the number of packets by 6.
65 x 6= 390
Now we take the total number of stamps minus the number of stamps in packets.
394 - 390 = 4
Therefore, there are four stamps left over.
Hope this helps!