16Hit1600
Advanced MathHardValue after repeated halving over a period

Advanced Math practice question

A quantity of 400 grams of a substance halves every 10 years. How many grams remain after 30 years?

Answer: 50

Three halvings: 400 → 200 → 100 → 50.

Common wrong answers

If you answered 100
100 is after 20 years.
If you answered 200
200 is after 10 years.
If you answered 133.3
133.3 divides 400 by 3.

More Advanced Math questions

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