A blood sample has 50,000 bacteria present. a drug fights the bacteria such that every hour the number of bacteria remaining, r(n), decreases by half. If r(n) is an exponential function of the number, n, of hours since the drug was taken, find the bacteria present four hours after administering the drug.

3125 bacteria

Step-by-step explanation:

Let r(0) be the initial amount of bacteria. Every hour, r(n) decreases by half. So, after one our new value for r(n) = (1/2)r(0). After two hours, r(n') =  (1/2)r(n) =  (1/2)(1/2)r(0) = (1/2)²r(0).

After n hours, r(n) = (1/2)ⁿr(0)

So when n = 4 hours and r(0) = 50,000, then

r(4) = (1/2)⁴r(0)

r(4) = (1/2)⁴ × 50,000

r(4) = (1/16) × 50,000

r(4) = 3125

So, after 4 hours, we have 3125 bacteria present.

walter needs to make at least 5 more cookies but no more than 40. 5 ≥ x ≥ 40;

step-by-step explanation:

walter has to make a minimum of 20 cookies. he already has 15 cookies made, so he must make 5 more to meet the minimum.

the maximum amount of cookies he can make is 55. he already has 15, so he has to make no more than 40 more cookies to meet the maximum.

is this part of a question or something