Question

Write the formula for the mean cell phone bill from March to September using sigma notation and determine that mean. Round your answer to the nearest cent.

Answer 1

Given a table represents the monthly cell phone bills.

We will find the mean cell phone bill from March to September

Mean = The sum divided by the number

We will find the sum using the sigma notation as follows:

`sum=\sum_{n\mathop{=}3}^9x_n=78+82+95+87+90+76+88=596`

And the number of the months from March to September = 7

So, the mean will be as follows:

`Mean=(596)/(7)=85.142857`

Rounding to the nearest cent. ​

So, the answer will be:

Mean = 85.14