A culture of yeast grows at a rate proportional to its size. If the initial population is 2000 cells and it doubles after 2 hours, answer the following questions. 1. Write an expression for the number of yeast cells after t hours. Answer: P (t) = 2. Find the number of yeast cells after 7 hours. Answer: 3. Find the rate at which the population of yeast cells is increasing at 7 hours. Answer (in cells per hour) :

Step-by-step explanation:

1) We would apply the formula,

y = ab^t

Where

a represents the initial amount of yeast.

t represents the doubling time.

From the information given

a = 2000

t = 2 hours

Since after 2 hours, the population of cells doubles, then

y = 2 * 2000 = 4000

Therefore

4000 = 2000 * b^2

Dividing through by 2000, it becomes

2 = b^2

Raising both sides of the equation by 1/2, it becomes

2^ (1/2) = b^2/2

b = 1.414

The equation becomes

y = 2000 (1.414) ^t

2) when t = 7 hours,

y = 2000 (1.414) ^7

y = 22604 cells

3) the rate is 22604/7 = 3229 cells per hour