Advanced Math practice question

Answer: 24

3,200 ÷ 400 = 8 = 2³, so three doublings are needed: 3 × 8 = 24 years.

Common wrong answers

If you answered 3

3 is the number of doublings, not the years.

If you answered 8

8 is one doubling period, which only reaches 800.

If you answered 64

64 is 8 × 8, multiplying the factor by the period.

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