Question

after the yeast population has doubled to 46 billion yeast cells, a green mold attacks your sourdough starter. This causes the yeast population to start dying by half every 2 hours.

How long would it be until there is just 1 yeast cell left? Please input your answer in hours with 2 decimal points.

Could you help me please

Answer 1

4.6*10^10(1/2)^(t/2) = 1 , where t is the number of hours
(1/2)^(t/2) = 1/(4.6*10^10)
(t/2) log .5 = log (1/(4.6*10^109))
t/2 = log (1/(4.6*10^109)) / log .5 = 35.4209
t = appr 70.84 hours