Question

Abdul has already spent 21 minutes on the phone, and he expects to spend 1 more minute with every phone call he routes. If he routes 20 phone calls, how much time will Abdul have spent on the phone in total?

A) 41 minutes
B) 61 minutes
C) 20 minutes
D) 40 minutes

Answer 1

Abdul will spend a total of 210 minutes on the phone.

Step-by-step explanation:

To find the total time Abdul will spend on the phone, we need to determine how much time each phone call will take. Since Abdul expects to spend 1 more minute with every phone call he routes, the time for each call can be represented by a sequence: 1, 2, 3, 4, ... up to 20. We can find the sum of this sequence by using the formula for the sum of an arithmetic series: S = n/2 * (first term + last term), where n is the number of terms in the sequence. In this case, n = 20 and first term = 1, last term = 20

Substituting these values into the formula, we get: S = 20/2 * (1 + 20) = 10 * 21 = 210 minutes

Therefore, Abdul will spend a total of 210 minutes on the phone.