Posted by **Angie** on Sunday, June 14, 2009 at 11:43am.

The formula N = 10(4') gives N, the number of bacteria present in a culture after t hours. How many hours

does it take for the number of bacteria to grow to 2,560?

a. 2 hours

b. 3 hours

c. 4 hours

d. 5 hours

The answer is c., but is there another way to find this answer besides substituting?