Question

The prices paid for a model of a new car are approximately normally distributed with a mean of $17,000 and a standard deviation of $500.

The price that is 3 standard deviations above the mean is $__

The price that is 2 standard deviations below the mean is $__

The percentage of buyers who paid between $16,500 and $17,500 is %__

The percentage of buyers who paid between $17,000 and $18,000 is %___

The percentage of buyers who paid less than $16,000 is %__

Answer 1

Explanation:

they are telling you the standard deviation , it's 500

then they ask, what's 3 times that. It's kinda obvious, when I put it in words like that so i'll let you do that math. 17,000 + (3*500) = ?

b)

17000 - (2*500) = ?

c)

This is the bell curve numbers of 1 deviation, it's 68%, if you don't recall

d)

it will be 1/2 of the 2nd deviation, or 95% * 0.5 = 47.5%

e)

this is the tiny amount outside of the main part of the 2 deviation on the bell curve.

5% is outside of the 2nd deviation. so it's half of that or 2.5%

Understand?????

:/