Answer:
(a) P = 3000·1.15^t
(b) 12,137
Explanation:
(a)
The equation gets filled in so it looks like ...
P = (initial amount) × (1 +growth rate)^t
where t is in units compatible with the growth rate.
P = 3000·1.15^t
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(b)
Midnight is 10 hours later than 2 p.m., so the quantity will be ...
P = 3000·1.15^10 ≈ 3000·4.045558 ≈ 12,137
There will be 12,137 bacteria at midnight.