Over the last three evenings, Kala received a total of 131 phone calls at the call center. The third evening, she received 4 times as many calls as the first evening. The second evening, she received 5 more calls than the first evening. How many phone calls did she receive each evening?

First evening, 21 calls. Second evening, 26 calls. Third evening, 84 calls.

Steps:

T = 4F

S = F + 5

131 = F + S + T

Substitute in the S and T equations;

131 = F + F + 5 + 4F

126 = 6F

F = 21

Then substitute F into both T and S equations;

T = 4 * 21

T = 84

S = 21 + 5

S = 26

The no. of call received on the first evening = 21

The no. of call received on the second evening = 26

The no. of call received on the third evening = 84

Step-by-step explanation:

Let the no. of call received on the first evening be x.

The no. of call received on the second evening = x + 5

The no. of call received on the third evening = 4x

x + x+5 + 4x = 131

6x + 5 = 131

6x = 131 - 5

6x = 126

x = 126/6

x = 21

The no. of call received on the first evening = 21

The no. of call received on the second evening = 21 + 5 = 26

The no. of call received on the third evening = 4*21 = 84