Question

A scientist counts 35 bacteria present in a culture and finds that the number of bacteria triples each hour. The function y = 35 ∙ 3x models the number of bacteria after x hours. Estimate when there will be about 550 bacteria in the culture.

Answer 1

After 5 hours

Explanation:

If a scientist counts 35 bacteria present in a culture and finds that the number of bacteria triples each hour and the function y = 35 ∙ 3x models the number of bacteria after x hours, in order to estimate when there will be about 550 bacteria in the culture we will substitute y = 550 into the modeled equation and calculate the value of x as shown;

If y = 35*3x

when y = 550

550 = 35*3x

Dividing both sides by 35;

550/35 = 35*3x/35

3x = 550/35

x = 550/3*35

x = 550/105

x = 5.24

This means that there will be 550 bacteria in the culture after approximately 5 hours