The tree frog population in your back yard doubles every two weeks. Currently, there are 10 frogs in your back yard. Assuming that there are 4 weeks in a month how many tree frogs will there be in 3 months?
So we want to know how many frogs will there be in 3 months if the frog population doubles every two weeks and there are 10 frogs in the start. So lets see how many weeks are there in 3 months if there is 4 weeks in one month: 3 * 4 weeks = 12 weeks. So every two weeks the population doubles and that means the population will double 6 times in 12 weeks. 20 + 40 + 80 + 160 + 320 640 = 1260 frogs.
