Question

At Sara's new job she spent $11.52, $6.48, $5.99, $14.00, and $9.50 on lunch the first week.

In the second week, she spent $4 more in total for the 5 lunches than the first week.
second


What is the increase in the mean for the second week compared to the first? Round the
answer to the nearest penny.​

Answer 1

A. 0.80

Explanation:

First, you need to find the mean of the cost of Sara's lunches the first week. The mean is the 'average,' and to find the average, add all of your terms and divide by the amount of terms.

`11.52+6.48+5.99+14+9.5\\18+5.99+14+9.5\\23.99+14+9.5\\37.99+9.5\\47.49`

Sarah's total cost for the first week was $47.49. Divide by your number of terms (5) for your average daily cost.

`(47.49)/(5) =9.498`

This can be rounded to $9.50.

For the next week, Sara spent $4 more in total than the first week. So, add $4 to your total.

`47.49+4=51.49`

Now, divide $51.49 by your number of terms (5) again to find your average for the second week.

`(51.49)/(5) =10.298`

This can be rounded to $10.30.

Find the difference.

`10.30-9.50=0.80`

Sara spent $0.80 more on average.