Question

Suppose that the amount of algae in a pond doubles every 4 hours. If the pond initially contains 90 pounds of algae, how much algae will be in the pond after 12 hours?

Answer 1

If it doubles every 4 hours, in 12 hours you will have 3 doublings.
2 * 2 * 2 = 8
90*8 = 720 pounds of algae