Question

A car salesperson offers you a car at the price of $17,995. You look up the mean sales price for thatcar and find out that the mean is $18,500 with a standard deviation of $450. What % of peoplebought the same car for less money than the salesperson is offering you?

Answer 1

Given:

The mean is $18500, and the standard deviation is $450.

To find:

What % of people bought the same car for less money than the salesperson is offering you.

Solution:

Here,

$\begin{gathered} \mu=18500 \\ \sigma=450 \end{gathered}$

We have to find P(x < 17995). So,

$\begin{gathered} P(x<17995)=P(\frac{x-\mu}{\sigma}<\frac{17995-18500}{450}) \\ =P(x<-1.12) \\ =0.1314 \end{gathered}$

Thus, the required probability is 13.14%.