In a renowned city, the average birth rate is 6 people every two seconds and the death rate is 3 people every two seconds. Estimate the size of the population net increase that occurs in one day.
Choices:
A) 129,500
B) 129,600
C) 129,700
D) 129,800
E) 129,900

Rationale: "this question can be modified so that the birth rate is given every m seconds and the death rate is given every n seconds . for this particular question : increase in the population every 2 seconds = 6 - 3 = 3 people . total 2 second interval in a day = 24 * 60 * 60 / 2 = 43,200 population increase = 43,200 * 3 = 129,600 . hence b ."
Answer: B