Question

The rate of change in the number of bacteria in a culture is proportional to the number present. In a certain laboratory experiment, a culture had 10,000 bacteria initially, 20,000 a time t1 minutes and 100,000 bacteria at (t1+10) minutes.

A) In terms of t only, find the number of bacteria in the culture a any time t minutes, t≥0.
B) How many bacteria were there after 20 minutes.
C) How many minutes had elasped when the 20,000 bacteria were observed

Answer 1

A 0.8t equal 10000 bacteria B. 160,000 bacteria C. 2.5 minutes

Explanation:

(20000-10000)/t equal to (100,000-10000)/(t+10)