Ten less than triple a number is 21

The length of time a person takes to decide which shoes to purchase is normally distributed with a mean of 8.21 minutes and a st

madam [21]

Answer:

4.55% probability that a randomly selected individual will take less than 5 minutes to select a shoe purchase.

Since Z > -2 and Z < 2, this outcome is not considered unusual.

Step-by-step explanation:

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

If $Z \leq 2$ or $Z \geq 2$ , the outcome X is considered to be unusual.

In this question:

$\mu = 8.21, \sigma = 1.9$

Find the probability that a randomly selected individual will take less than 5 minutes to select a shoe purchase.

This is the pvalue of Z when X = 5. So

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{5 - 8.21}{1.9}$

$Z = -1.69$

$Z = -1.69$ has a pvalue of 0.0455.

4.55% probability that a randomly selected individual will take less than 5 minutes to select a shoe purchase.

Since Z > -2 and Z < 2, this outcome is not considered unusual.

8 0

3 years ago

How do you decide which variable to isolate in order to use the substitution method to solve a system of linear equation?

Kazeer [188]

It doesn’t really matter which variable you isolate first but usually you would use the one that’s by itself already. like for example one of the equations was y = 8. you would already have your y solve for so you would just have to plug that in for y in the other equation. personally, i usually do x first unless one of the equations has either x or y by itself already. i think its easier to just do x first and then solve for y after that, but it just depends on what the equations are; sometimes it might be easier to just do y first. hope this helps!

5 0

3 years ago

What is the volume of a cylinder with base radius 4 and height 5?

lord [1]

Answer:

hey

Step-by-step explanation:

yep

3 0

3 years ago

Read 2 more answers

A house number is displayed on a plaque in the shape of a regular 7-sided polygon. The area of the plaque is 70 squared inches.

Svetllana [295]

Answer:

The perimeter of the plaque is 28 inches.

Step-by-step explanation:

Given : A house number is displayed on a plaque in the shape of a regular 7-sided polygon. The area of the plaque is 70 squared inches. The perpendicular distance from a side to the center is 5 inches to the nearest inch.

To find : What is the perimeter of the plaque?

Solution :

The 7-sided polygon can be divided into seven triangles whose height, h is equal to the perpendicular distance from each side to the center.

The base of each triangle is equal to the length of a side, s.

The area of each triangle is $A=\frac{1}{2}\times s\times h$