To find the area of the resulting surface when the given curve y = 1/4x^2 - 1/2 ln(x) is rotated about the y-axis, we can use the Surface of Revolution formula:
Surface Area = 2 * pi * ∫[x * sqrt(1 + (dy/dx)^2)] dx from a to b
Here, a = 3 and b = 5.
First, we need to find the derivative of y with respect to x (dy/dx):
y = 1/4x^2 - 1/2 ln(x)
dy/dx = (1/4 * 2x) - (1/2 * 1/x) = x/2 - 1/(2x)
Now, let's plug this into the Surface of Revolution formula:
Surface Area = 2 * pi * ∫[x * sqrt(1 + (x/2 - 1/(2x))^2)] dx from 3 to 5
We will now integrate the expression within the brackets with respect to x from 3 to 5. This might be challenging to solve analytically, so we may need to use a numerical integration method or a calculator to find the exact value.
Once the integration is completed, you will obtain the surface area of the curve when rotated about the y-axis.
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One angle of a triangle measures 40°. The other two angles are in a ratio of 5:9. What are the measures of those two angles?
Answer:
50 and 90
Step-by-step explanation:
(180-40)/(5 + 9) = 10
=> 50 and 90
what is the difference between ka and kb and what is the mathematical relationship between them?
Ka and Kb are both acid-base equilibrium constants, but they apply to different types of reactions. Ka (acid dissociation constant) is used to describe the dissociation of an acid in water, while Kb (base dissociation constant) is used to describe the dissociation of a base in water.
Specifically, Ka is a measure of the strength of an acid in terms of how easily it donates a proton (H+) to a solvent like water. A higher Ka value indicates a stronger acid, while a lower Ka value indicates a weaker acid. Kb, on the other hand, is a measure of the strength of a base in terms of how easily it accepts a proton (H+) from a solvent like water. A higher Kb value indicates a stronger base, while a lower Kb value indicates a weaker base. There is a mathematical relationship between Ka and Kb for conjugate acid-base pairs, which are molecules or ions that differ by the presence or absence of a single proton. The relationship is expressed by the equation: Ka x Kb = Kw, where Kw is the ion product constant for water, which is 1.0 x 10⁻¹⁴ at 25°C. This relationship shows that the stronger the acid, the weaker its conjugate base, and vice versa.
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WILL GIVE 30 points. The GRE is an entrance exam that many students are required to take in order to apply to graduate school. In 2014, the combined scores for
the Verbal and Quantitative sections were approximately normally distributed with a mean of 310 and a
standard deviat o of 12.
What is the probability that a randomly selected score is greater than 334? Write your answer as a decimal.
Answer:
The answer is 0.0228. Have a good day!
Answer:it’s 0.025
Step-by-step explanation:
Given that AC is a diameter of the circle above and that mŁABD= 649, find m2DBC.
A. 26°
B. 369
C. 46°
D.
649
Answer: D
Step-by-step explanation:
You can visually see that they are equal to each other, since the dimater goes directly through the center
Answer:
A.
Step-by-step explanation:
what angles of rotational symmetry are there for a regular pentagon
Answer:
a regular pentagon has 72 degrees
Step-by-step explanation:
I need the answer quick
The number of orange tiles that should be bought for a pool with a side length of n tiles will be 2n - 1. This was illustrated in the square tiles.
How to illustrate the information?It should be noted that a square simply means a quadrilateral that has all the sides equal. It should be noted that in a square, the sides contain four right angles. This illustrates that the total angle that will be in a square is 360°.
From the information given, the dimensions of the pool are n ×n. In the given information, we are hit given what n is in the question.
Therefore since the tiles that are given is a square, then the number of orange tiles that should be bought for a pool with a side length of n tiles will be:
= (2 × n) - 1
= 2n - 1
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how to tell if riemann sum is overestimate or underestimate
Answer: See below
Step-by-step explanation:
Using a graphing approach:
If the graph is increasing, then the left-sum is an underestimate of the actual value and the right-sum is an overestimate
If the curve is decreasing then the right-sums are underestimates and the left-sums are overestimates
(-3+7i)(1-2i) can you help me with the answer to this
Answer:
11 + 13i
Step-by-step explanation:
A must know is that
\( \sqrt{i} = - 1\)
Complex numbers
1st: foil the equations
\( - 3(1 - 2i) + 7i(1 - 2i)\)
\( - 3 + 6i + 7i- 14 {i}^{2} \)
2nd Combine like terms and substitute
\(i ^{2} for \: - 1\)
\( - 3 + 14 + 13i\)
\(11 + 13i\)
How would I solve \(8^{3/2} * 2^{3/2}\) ?
11. Engineering The maximum load for a certain elevator is 2000 pounds. The total
weight of the passengers on the elevator is 1400 pounds. A delivery man who weighs
243 pounds enters the elevator with a crate of weight w. Write, solve, and graph an
inequality to show the values of w that will not exceed the weight limit of the elevator.
The inequality to show the values of [w] that will not exceed the weight limit of the elevator is w + 1643 ≤ 2000. On solving the inequality, we get w ≤ 357. The graph of the inequality is attached.
What is inequality?In mathematics, an inequality is a relation which makes a non-equal comparison between two numbers or other mathematical expressions. It is used most often to compare two numbers on the number line by their size.An inequality is a mathematical relationship between two expressions and is represented using one of the following -≤ : less than or equal to
≥ : greater than or equal to
< : less than
> : greater than
≠ : not equal to
Given is the maximum load for a certain elevator is 2000 pounds. The total weight of the passengers on the elevator is 1400 pounds. A delivery man who weighs 243 pounds enters the elevator with a crate of weight [w].
We can write the inequality as follows -1400 + 243 + w ≤ 2000
w + 1643 ≤ 2000
Solving the inequality, we get -w + 1643 ≤ 2000
w ≤ 2000 - 1643
w ≤ 357
Refer to the graph attached.Therefore, the inequality to show the values of [w] that will not exceed the weight limit of the elevator is w + 1643 ≤ 2000. On solving the inequality, we get w ≤ 357. The graph of the inequality is attached.
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Consider the following first order, linear, constant coefficient differential equation, y(t) = ay(t) + bu(t) y(0) = y. where a <0 and 670 are real constants. (a) (4pt) Assume y(t) = c(t)eat and show that the total solution can be expressed as y(t) = ex yo + [cate=)bu(r)dr.
This is the desired expression for the total solution.
To solve the differential equation, we assume that the solution is of the form y(t) = c(t)eat. Then, we have:
y'(t) = c'(t)eat + aceat
y(0) = c(0)e0a = y
Substituting these into the differential equation, we get:
c'(t)eat + aceat = a(c(t)eat) + bu(t)
Simplifying this equation, we get:
c'(t) = bu(t)e-at
Integrating both sides from 0 to t, we get:
c(t) - c(0) = ∫0t bu(r)e-ar dr
Multiplying both sides by eat, we get:
y(t) - y = e-at(c(0) + ∫0t bu(r)e-ar dr)
Rewriting the right-hand side in terms of a constant c and a function h(t), we get:
y(t) = e-at y + c ∫0t bu(r)e-ar dr
where c = eay and h(t) = bu(t)e-at. This is the desired expression for the total solution.
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please somebody else help me to do . I will mark the correct answer as a brainiest
there is your answer follow and mark me as brainliest
in a casino, you play the following game: you choose a number between 1 and 6 and then throw 3 fair six-sided dice. after tossing, for each die showing your chosen number, the casino pays you $1. In order to play this game, you have to pay the casino a stake of S1 Let X denote your net win after one round of gambling (i.e., the payment received from the casino minus your stake) (a) Determine the state space Sx of X (b) Compute the probability mass function px of X (c) Compute the expected value E[X] of X (d) In general, a game is called a fair game if the net win of the gambler is 0 "on average" Is the above game a fair game? If not, what should be the stake of the gambler in order to make this a fair game? Give a reason for your answer.
By using the concept of probability, it can be calculated that
a) State space S(x) = {-1, 0, 1, 2}
b) The required probability mass function is
P(X = -1) = \(\frac{125}{216}\)
P(X = 0) \(= \frac{25}{72}\)
P(X = 1) \(= \frac{5}{72}\)
P(X = 2) \(= \frac{1}{216}\)
c) Expected value of X = -0.5
d) the stake of the gambler in order to make this a fair game is $0.5
What is probability?
Probability gives us the information about how likely an event is going to occur
Probability is calculated by Number of favourable outcomes divided by the total number of outcomes.
Probality of any event is greater than or equal to zero and less than or equal to 1.
Probability of sure event is 1 and probability of unsure event is 0.
a) Let a number n be chosen between 1 and 6
Three fair six sided dice are thrown
The following cases can occur
1) Number n occur on none of the three dice
2) Number n occur on one dice
3) Number n occur on two dice
4) Number n occur on three dice
Let X denote your net win after one round of gambling (i.e., the payment received from the casino minus your stake)
1) X = 0 -1 = -1
2) X = 1 - 1 = 0
3) X = 2 - 1 = 1
4) X = 3 - 1 = 2
State space S(x) = {-1, 0, 1, 2}
b) P(X = -1) = \({3 \choose 0}(\frac{1}{6})^0(\frac{5}{6})^3 = (\frac{5}{6})^3 = \frac{125}{216}\)
P(X = 0) = \({3 \choose 1})(\frac{1}{6})(\frac{5}{6})^2 = \frac{25}{72}\)
P(X = 1) = \({3 \choose 2}(\frac{1}{6})^2\frac{5}{6} = \frac{5}{72}\)
P(X = 2) = \({3 \choose 3}(\frac{1}{6})^3(\frac{5}{6})^0 = \frac{1}{216}\)
The required probability mass function is
P(X = -1) = \(\frac{125}{216}\)
P(X = 0) \(= \frac{25}{72}\)
P(X = 1) \(= \frac{5}{72}\)
P(X = 2) \(= \frac{1}{216}\)
c) Expected value of X = \(-1 \times \frac{125}{216} + 0 \times \frac{25}{72} + 1 \times \frac{5}{72} + 2\times \frac{1}{216}\)
= \(\frac{-125 + 0 + 15 +2}{216}\\\)
= \(-\frac{108}{125}\)
= -0.5
d) The gambler looses $0.5 on a average
So this is not a fair game
Let the stake of the gambler in order to make this a fair game be t
By the problem,
-0.5 + t = 0
t = 0 + 0.5
t = $0.5
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I NEED HELP WITH THIS !
1. you purchase 6 bunches of celery, each weighing 2 pounds. how many 2 ounce servings can be made to serve with buffalo wings? celery has a 75% yield.
72, 2-ounce servings can be made to serve with buffalo wings.
Given that 6 bunches of celery each weighs 2 pounds. We have to find out how many 2-ounce servings can be made to serve with buffalo wings. Also, celery has a 75% yield.
\(Total weight of celery = 6 bunches * 2 pounds\)
each = 12 pounds
Total weight of celery in ounces
\(= 12 pounds * 16 ounces\)
\(= 192 ounces\)
75% yield of celery means that 75% of the celery is edible.
The edible portion of celery
= 75% of 192 ounces
\(= (75/100)*192 = 144 ounces\)
Now, as we have to find the number of 2-ounce servings that can be made, we need to divide the edible portion of celery by 2 ounces each. Thus, the number of 2-ounce servings can be made to serve with buffalo wings
\(= 144/2 = 72.\)
Hence, 72 2-ounce servings can be made to serve with buffalo wings.
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at time zero, there are 10.0 grams of w - 187. if the half - life is 23.9 hours, how much will be present at the end of one day? two days? seven days?
There are 10.0g of w – 187 at time zero. If the half-life is 23.9 hours, then the amount of quantity for: 1 day = 4.98 g, 2 day = 2.48 g, on 7th day = 0.0765 g.
A drug's half-life is the duration it takes for the amount of its active ingredient to halve in your body. A radioactive isotope's half-life is the length of time it takes for one half of the isotope to decay. A particular radioactive isotope's half-life is constant; it is unaffected by environmental factors and is unrelated to the starting concentration of that isotope.
time 24.0 hr / 23.9 hr/half-life = 1.0042 half-lives
One day half-life is:
= (1/2)^1.0042
= 0.4985465
= 4.98 g
For Two days:
= (1/2)^2.0084
= 0.2485486
= 2.48 g
For Seven days:
= (1/2)^7.0294
= 0.0076549
= 0.0765 g
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(a) In the figure below, state two angles subtended by each of the following arcs at the circumference; (1) PT (iii) SR P O (ii) TS (iv) RQ S R (b) What can you say about each pair of angles you have stated in question 2(a) above?
The measure of each angle is equal to the measure of its supplementary angle.
What is angle?Angle is a figure formed by two rays sharing a common endpoint. It is typically measured in degrees, with a full circle measuring 360°. Angles are used to describe the direction of lines and the relationships between them. Angles can also be used to describe the shape of objects and figures.
(1) Angles subtended by arc PT at the circumference are ∠POT and ∠PTQ.
(2) Angles subtended by arc TS at the circumference are ∠TSQ and ∠TSR.
(3) Angles subtended by arc SR at the circumference are ∠SRP and ∠SRQ.
(4) Angles subtended by arc RQ at the circumference are ∠RQP and ∠RQS.
The angles stated in question 2(a) above are all pairs of supplementary angles, which means that they add up to 180°. This means that the measure of each angle is equal to the measure of its supplementary angle.
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(a) (i) Angles subtended by arc PT at the circumference are ∠POT and ∠PTQ.
(ii) Angles subtended by arc TS at the circumference are ∠TSQ and ∠TSR.
(iii) Angles subtended by arc SR at the circumference are ∠SRP and ∠SRQ.
(iv) Angles subtended by arc RQ at the circumference are ∠RQP and ∠RQS.
(b) The angles stated in question 2(a) above are all pairs of supplementary angles, which means that they add up to 180°.
What is angle?Angle is a figure formed by two rays sharing a common endpoint. It is typically measured in degrees, with a full circle measuring 360°. Angles are used to describe the direction of lines and the relationships between them. Angles can also be used to describe the shape of objects and figures.
The angles stated in question 2(a) above are all pairs of supplementary angles, which means that they add up to 180°. This means that the measure of each angle is equal to the measure of its supplementary angle.
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Use the Rational Zeros Theorem to list all possible zero(s) of the function \( f(x)=x^{3}-4 x^{2}+5 x+6 \). Enter the possible zeros separated by commas.
The possible zeros of the function f(x)=x³- 4x² + 5x + 6 are
-6, -3, -2, -1, 1, 2, 3, 6.How to find the zerosTo find the possible zeros of the function f(x)=x³- 4x² + 5x + 6 using the Rational Zeros Theorem, we need to consider the factors of the constant term (6) divided by the factors of the leading coefficient (1).
The factors of 6 are: ±1, ±2, ±3, ±6
The factors of 1 (leading coefficient) are: ±1
Using the Rational Zeros Theorem, the possible zeros can be obtained by taking all possible combinations of the factors and their negations. Therefore, the possible zeros are:
±1, ±2, ±3, ±6
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anyone a single pringle and i need help 500 divided by 23 times 3
Answer:
65.21739130434783
Step-by-step explanation:
1. What is the slope of the line?
2. What is the opportunity cost of producing 3 trucks?
3. What do you notice about the relationship between the
number of cars given up and the number of trucks
gained?
4. Discuss the relationship between slope and opportunity
cost?
I NEED THIS ASAP
1. The slope of the line is -3/4. 2. The opportunity cost of producing 3 trucks is - 2/3. 3. The opportunity cost of 3 trucks is equal to the cost of -2/3 cars.
What is opportunity cost?Opportunity cost is the advantage that was lost because a particular option was not selected.
It is necessary to weigh the advantages and disadvantages of each choice offered in order to correctly assess opportunity costs.
Opportunity costs have a value that can help people and businesses make more lucrative decisions.
Opportunity cost is a wholly internal expense that is only utilised for strategic consideration; it is not included in accounting profit and is not reported externally.
The given coordinates of the line are:
(x1, y1) = (0, 3)
(x2, y2) = (4, 0)
The slope is given by the formula:
m = y2 - y1 / x2 - x1
Substituting the values of the coordinates we have:
m = (0 - 3) / (4 - 0)
m = - 3/4
The slope of the line is -3/4.
b. The opportunity cost is calculated as:
Opportunity cost = (y1 - y2) / (x1 - x2)
For producing 3 trucks, the cars that need to be produced are 1.
Thus, (x2, y2) = (3, 1)
while, (x1, y1) = (0, 3)
The opportunity cost is:
Opportunity cost = (3 - 1) / (0 - 3) = - 2/3
c. The opportunity cost of 3 trucks is equal to the cost of -2/3 cars.
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64.3- 3 x 23 - 2 is what.
Answer: -6.7
Step-by-step explanation:
64.3−(3)(23)−2
=−6.7
Answer:
-6.7
Step-by-step explanation:
1/3 (x+2)=-2/5 (x-9) and x=4
Answer:
2 = 2 (Identity)
Step-by-step explanation:
1/3 (x+2)=-2/5 (x-9) and x=4
Follow distributive property
1/3x + 2/3 = -2/5x + 18/5
Replace x for 4
1/3(4) + 2/3 = -2/5(4) + 18/5
4/3 + 2/3 = -8/5 + 18/5
Add like terms
6/3 = 10/5
Simplify
2 = 2
Also known as Identity
You work in Social Media as a consultant. You are working on a new report to examine trends in Social Media usage and age. You conducted a survey of 1072 people randomly selected in the United States (you limited minimum age to 12). The file "Usagef.xlsx" has results of the survey. For each Social Media platform you have a 0/1 variable indicating whether or not the person said they used the platform in the last 6 months. For each of those variables, 1 means the person did use the platform in the last 6 months and 0 means they did not. You also have the age of each respondent calculated based on birth date (so 43.56 means the individual is 43.56 years old). There are two additional variables:
Young adult: 1=respondent is under 35; 0=respondent is 35 or over.
Platforms Used: The total number of Social Media platforms used in the last 6 months.
Please use this information and the data in the excel spreadsheet "Usagef.xlsx" to answer the following questions:
Assuming the sample is a random sample of the U.S. population, what is the upper bound of the 95% confidence interval for the average age in the U.S?
The upper bound of the 95% confidence interval for the average age in the U.S. is 48.29 years.
To determine the upper bound of the 95% confidence interval for the average age in the U.S., we can use the sample data from the survey. The sample size is 1072 people, randomly selected from the U.S. population, with a minimum age of 12. By calculating the average age of the respondents, we can estimate the average age of the entire U.S. population.
Using the given information that the average age of the respondents is 43.56 years, and assuming that the sample is representative of the population, we can calculate the standard error. The standard error measures the variability of the sample mean and indicates how much the sample mean might deviate from the population mean.
Using statistical methods, we can calculate the standard error and construct a confidence interval around the sample mean. The upper bound of the 95% confidence interval represents the highest plausible value for the population average age based on the sample data.
Therefore, based on the provided information and calculations, the upper bound of the 95% confidence interval for the average age in the U.S. is 48.29 years.
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A force of 250 N is applied to an object that accelerates at a rate of 5 m/sec^2. What is the mass of the object?
======================================================
Work Shown:
F = ma
250 = m*5
250/5 = m
50 = m
m = 50
The mass of the object is 50 kg
11+x=-7
im using the wall thing with the line though the =.
Answer:
x= -7-11
x=-18
Step-by-step explanation:
Given: AB ∥ DC , m CB =62°, m∠DAB=104° Find: m∠DEA, m∠ADB
Answer:
m∠DEA = 62°
m∠ADB (arc) = 194°
Angle ∠ADB = 21°.
Step-by-step explanation:
The given information are;
\(AB\left | \right |DC\), m CB (arc) = 62°, m∠DAB (arc) = 104°
arc∠BCD = 360° - 104° = 256°
m DC (arc) = arc∠BCD - arc CB = 256° - 62° (Sum of angles)
Therefore DC (arc) = 194°
m DA ≅ m CB = 62° (Parallel lines congruent arc theorem. Arc between two parallel lines)
m∠DEA = 1/2×(arc DA + arc CB) = 1/2×(62° + 62°) =62°
m∠DEA = 62°
Arc AB = m∠DAB (arc) - m DA = 104° - 62° = 42°
m∠ADB (arc) = 360 - m∠DAB (arc) - m CB (arc) (Sum of angles around a circle or point)
∴ m∠ADB (arc) = 360 - 104 - 62 = 194°
m∠ADB (arc) = 194°
Angle ADB = subtended by arc AB = ∴1/2×arc AB
Angle ∠ADB = 42/2 = 21°.
Angle = 21°
find a basis of the corresponding homo geneous equation
x+y+z+w+ u+v= 0
x-y+z=1
and find an expression of all solutions
To find a basis for the corresponding homogeneous equation and an expression of all solutions. Therefore, a basis for the corresponding homogeneous equation is the set.
we need to solve the system of equations and find the parametric form of the solutions.
Given the system of equations:
x + y + z + w + u + v = 0 -- (1)
x - y + z = 1 -- (2)
To find the basis for the homogeneous equation, we need to solve the system by setting the right-hand side of equation (2) to 0:
x - y + z = 0
Now we have the following system of equations:
x + y + z + w + u + v = 0 -- (1)
x - y + z = 0 -- (3)
We can rewrite equation (3) as:
x = y - z
Substituting this into equation (1):
(y - z) + y + z + w + u + v = 0
2y + w + u + v = 0
Now, we can express the variables in terms of parameters. Let's choose two parameters, say t and s, to represent y and w, respectively:
y = t
w = s
Then, substituting these values back into the equation:
2t + s + u + v = 0
Now we have the parametric form of the system of equations:
x = t - z
y = t
z = z
w = s
u = -2t - s
v = -2t - s
To express all the solutions, we can combine the parametric equations:
(x, y, z, w, u, v) = (t - z, t, z, s, -2t - s, -2t - s)
Therefore, a basis for the corresponding homogeneous equation is the set:
{ (1, 0, 0, 0, -2, -2), (-1, 1, 0, 0, -2, -2), (0, 0, 1, 0, -2, -2) }
And the expression of all solutions is given by:
(x, y, z, w, u, v) = t(1, 0, 0, 0, -2, -2) + s(-1, 1, 0, 0, -2, -2) + z(0, 0, 1, 0, -2, -2)
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 I REALLY NEED HELP WITH THIS!!
Determine the angles of a rotation
A) 90º clockwise
B) 90º counterclockwise
C) 180º
D) 270º clockwise
E) 270º counterclockwise
is 2 correct answers ❗️ 
An angle of rotation is the measure of the amount that a figure is rotated about a fixed point called a point of rotation.
Explain the angles of a rotation?Movement in circles is rotation. The daily rotation of the Earth about its axis is an example of a rotation, which is the movement of something through one full circle. [ + of] Alternative Words: wheel, revolving, revolution more words for rotationAngle of rotation =m = m is the product of the number of central angles and the measure of a single central angle to get the angle of rotation between two points or vertices.The definition of the direction of a rotation in a plane in terms of the rotation's angle. The rotation will move counterclockwise if the angle of rotation is positive. The rotation will move counterclockwise if the angle of rotation is negativeThe angle of a rotation is 90 clockwise
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Mhanifa can you please help? I need this done asap and I'm almost done!
Answer:
See attached
All points are plotted and we see the figure we got
8. Rectangle
We can visually confirm that
Opposite sides are parallel and congruentAll interior angles angles are right angles---------------------------------------------------------------------------
9. Square
We can visually confirm that
All sides are congruentAll interior angles angles are right angles12 points if someone gets it right.
You randomly draw twice from this deck of cards. What is the probability of drawing a 7, then drawing a prime number, replacing the first card? write you answer as a fraction.
Numbers: 7 6 4 9 4 7 9
Answer:
4/49
Step-by-step explanation:
7, 6, 4, 9, 4, 7, 9
total number of cards: 7
number of 7's: 2
First drawing:
p(7) = 2/7
Replace the 7.
total number of cards: 7
number of prime numbers: 2 (only the 7's are prime numbers)
p(7) = 2/7
The events are independent, so the overall probability is the product of the individual probabilities.
p(7 then prime) = 2/7 × 2/7 = 4/49