Answer:
first evening = 21 phone calls
second evening = 11 phone calls
third evening = 84 phone calls
Step-by-step explanation:
Total phone calls = 116
Let
Number of calls in the first evening = x
The second evening = x - 10
The third evening = 4x
Total phone calls = first evening + second evening + third evening
116 = x + (x - 10) + 4x
116 = x + x - 10 + 4x
116 + 10 = 6x
126 = 6x
x = 126 / 6
x = 21 phone calls
Number of calls in the first evening = x
= 21 phone calls
The second evening = x - 10
= 21 - 10
= 11 phone calls
The third evening = 4x
= 4(21)
= 84 phone calls