Question

A yeast grows at a rate proportional to its present size.if the original amount doubles in two hours in how many hours will it triple

Answer 1

A yeast grows at a rate proportional to its present size
----> amount = a e^(kt), where a is the initial amount and t is in hours

given: when t = 2, a = 1, and Amount = 2
2 = 1 e^(2k)
take ln of both sides and use log rules
ln2 = 2k
k = ln2/2

amount = 1 e^((ln2/2)t)
for tripling:
3 = e^ ((ln2/2)t) , solve for t, let me know what you get