Question

Use the table to write and solve an equation to find the number of

cars c that a salesperson needs to sell in the fourth month so that
the salesperson’s mean number of cars sold per month is 10.
Month 1 2 3 4
Cars Sold 8 9 12 c

Answer 1

`c = 11`

Explanation:

Given

`Cars\ Sold:-: 8; 9; 12; c`

Required

What value of c makes the mean = 10

Mean is calculated as

`Mean = (\sum x)/(n)`

In this case;

Mean = 10 and n = 4;

So, we have:

`10 = (8+ 9 + 12 + c)/(4)`

`10 = (29+ c)/(4)`

Multiply both sides by 4

`10 * 4 = 29 + c`

`40 = 29 + c`

Solve for c

`c = 40 - 29`

`c = 11`