17 There are 50 bacteria in a Petri dish and the number of b

17. There are 50 bacteria in a Petri dish and the number of bacteria triples every 7 hours (a) Write a function that gives the number of bacteria, BO),afterthours How many hours will it take for the num will suffice.) ber of bacteria to reach 500? (A formula

Solution

y= a b^t

3a = a b⁷

b⁷=3

b=3^1/7

y=50 (3)^t/7

b.500=50(3)^t/7

10=3^t/7

log 10=(t/7)log 3

7log 10/log 3=t

t=7/log 3