Advanced Math practice question

Answer: 24

640 → 320 → 160 → 80 → 40 is four halvings: 4 × 6 = 24 hours.

Common wrong answers

If you answered 4

4 is the number of halvings, not hours.

If you answered 18

18 hours is three halvings, leaving 80 mg.

If you answered 96

96 multiplies the ratio 16 by 6, mistaking the ratio for the number of halvings.

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