Evaluate the following expression if y = 4

PLEASE HELP I HAVE NO IDEA WHAT IM DOING!!!

algol13

Answer: 28.26

Step-by-step explanation:

What your looking for is called the annulus (or the difference of two concentric circles). You can find the annulus by subtracting the area of the inner circle from the area of the outer circle. Volume of a circle= πr²

You are given the diameter in these problems, so you need radius.

For the first circle (8 in one) :

8/2=4 r=4

A=3.14(4)²

A=50.24

For the second one (10 in one) :

10/2=5 r=5

A=3.14(5)²

A=78.5

To find the measure of the annulus, you subtract those numbers, getting 28.26

8 0

3 years ago

A square lawn has area 98 ft². A sprinkler placed at the center of the lawn sprays water in a circular pattern as

torisob [31]

The radius of the circle exists approximately 4.95 feet.

<h3>How to estimate the radius of the circle?</h3>

Given the area of the square as A = 98 ft²

The side length of the square choice is equivalent to the diameter of the circle.

First, we must obtain the length of the square.

Area of a square $= L^2$

98 = L²

L = √98

L = 9.89 ft

Thus the diameter of the circle exists at 9.89 ft

radius = diameter/2

radius = 9.89/2

radius ≈ 4.95 feet

Therefore the radius of the circle exists approximately 4.95 feet.

To learn more about the radius of circle refer to:

brainly.com/question/19568457

#SPJ9

3 0

1 year ago

Item 1 A bag contains 7 blue cards, 4 green cards, 6 red cards, and 8 yellow cards. You randomly choose a card. a. How many poss

egoroff_w [7]

Answer:

4 possible outcomes

Step-by-step explanation:

we know that

The probability of an event is the ratio of the size of the event space to the size of the sample space.

The size of the sample space is the total number of possible outcomes

The event space is the number of outcomes in the event you are interested in.

so

Let

x------> size of the event space

y-----> size of the sample space

so

$P=\frac{x}{y}$

In this problem

<em>The probability of choose a blue card is </em>

$x=7$

$y=7+4+6+8=25$

substitute

$P=\frac{7}{25}$

<em>The probability of choose a green card is </em>

$x=4$

$y=7+4+6+8=25$

substitute

$P=\frac{4}{25}$

<em>The probability of choose a red card is </em>

$x=6$

$y=7+4+6+8=25$

substitute

$P=\frac{6}{25}$

<em>The probability of choose a yellow card is </em>

$x=8$

$y=7+4+6+8=25$

substitute

$P=\frac{8}{25}$

The sum of the probabilities of the 4 possible outcomes is equal to

$\frac{7}{25}+\frac{4}{25}+\frac{6}{25}+\frac{8}{25}=\frac{25}{25}$ ----> represent the 100%

4 0

3 years ago

The national average sat score (for verbal and math) is 1028. if we assume a normal distribution with standard deviation 92, wha

elena55 [62]

Let X be the national sat score. X follows normal distribution with mean μ =1028, standard deviation σ = 92

The 90th percentile score is nothing but the x value for which area below x is 90%.

To find 90th percentile we will find find z score such that probability below z is 0.9

P(Z <z) = 0.9

Using excel function to find z score corresponding to probability 0.9 is

z = NORM.S.INV(0.9) = 1.28

z =1.28

Now convert z score into x value using the formula

x = z *σ + μ

x = 1.28 * 92 + 1028

x = 1145.76

The 90th percentile score value is 1145.76

The probability that randomly selected score exceeds 1200 is

P(X > 1200)

Z score corresponding to x=1200 is

z = $\frac{x - mean}{standard deviation}$

z = $\frac{1200-1028}{92}$

z = 1.8695 ~ 1.87

P(Z > 1.87 ) = 1 - P(Z < 1.87)

Using z-score table to find probability z < 1.87

P(Z < 1.87) = 0.9693

P(Z > 1.87) = 1 - 0.9693

P(Z > 1.87) = 0.0307

The probability that a randomly selected score exceeds 1200 is 0.0307

5 0

3 years ago

WILL GIVE BRAINLIEST

tester [92]

The answer would be
D) 40

8 0

3 years ago

​Evaluate the following expression if y = 4

Evaluate the following expression if y = 4