Answer:
Bobby answers 30% of all phone calls.
Explanation:
To determine the proportion of calls that Bobby answers in the call center, knowing that Charlie handles one third as many calls as him, and that Alex handles six times as many calls as Charlie, the following equivalence must be made:
A = 6 C (1/3B x 6 = 2B)
B = B
C = 1/3 B
2B + B + 1/3 B = 100
3 1/3 B = 100
3.33 B = 100
B = 100 / 3.33
B = 30
Therefore, Bobby answers 30% of calls, Alex answers 60% and Charlie 10%.