A culture of 50 bacteria doubles every 4 hours. How many bacteria are there after 12 hours?
Answer and explanation
Correct answer: B. 400
- Step 1: The number of doublings is 12 / 4 = 3.
- Step 2: N = 50 x 2^3 = 400.
Answer
400.
Why not the others: '300' multiplies by 2n instead of 2^n; '200' applies one doubling too few; '800' applies one doubling too many.
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