Question

Set of data has a normal distribution with a mean of 56 and a standard deviation of 7. Find the percent of data within the following interval.
from 35 to 77

SOMEONE PLEASE HELP

Answer 1

Answer:

.99815

which is about

99.815%

Step-by-step explanation:

we are looking for 35<x<77

We need to find (what I think is called) the z score which is acheieved through what I'm pretty sure is called standardizing

What we do is subtract the mean and then divide by the standard deviation

so for 35 we have

(35-56)/7= -3.29

due to the fact that the normal distribution is symmetric this is equal to 1-p(3.29)

to find p(3.29) grab a ztable and get p(3.29)= .9995

1-.9995= .0005

For 77 we have

(77-56)/7=3

grab a ztable and find the 3= .99865

Finally subtract these two to get the final answer

.99865-.0005= .99815