Answer:
- 29
- 80
- 20
Explanation:
Since the problem description tells you the numbers in terms of the calls received on the third evening, let that value be represented by x. Then we have ...
first evening's calls: x + 9
second evening's calls: 4x
third evening's calls: x
Total calls = 129 = (x +9) +4x +x = 6x +9
x = (129 -9)/6 = 20
Maria received 29 calls the first evening, 80 calls the second evening, and 20 calls the third evening.