Question

Over the last three evenings, Teresa received a total of 87 phone calls at the call center. the third evening she received 2 times as many calls as the second evening. The first evening, she received 7 more calls than the second evening. How many phone calls did she receive each evening.

Answer 1

Assume that the phone calls of the second evening is x

Since the phone calls of the third evening is two times the second,

Then the third evening is 2x

Since the first evening is 7 more than the second,

Then the first evening is x + 7

Since she received a total of 87 phone calls in the three evening

Add them and equate the answer by 87

`x+7+x+2x=87`

Add the like terms in the left side

`4x+7=87`

Subtract 7 from both sides

`\begin{gathered} 4x-7-7=87-7 \\ 4x=80 \end{gathered}`

Divide both sides by 4 to find x

`\begin{gathered} (4x)/(4)=(80)/(4) \\ x=20 \end{gathered}`

Since x represents the number of phone calls in the second evening, 2x represents the third evening, and x + 7 represents the first evening

So:

1st evening = 20 + 7 = 27 phone calls

2nd evening = 20 phone calls

3rd evening = 2 (20) = 40 phone calls