A certain number of bacteria are in a petri dish. If the growth rate is 2.7 percent per hour, how many hours will it take the bacteria to double in number?

Time = log (end amount) - log (bgng amt) / log (1 + rate)

If we're waiting for it to double, then we'll say beginning amount = 100 and ending amount = 200.

time = [log (200) - log (100) ] / log (1.027)

time = 2.3010299957 - 2 / 0.011570443597

time =.3010299957 / 0.011570443597

time = 26.0171525125 hours