16Hit1600
Advanced MathEasy–MediumDoubling three times

Advanced Math practice question

A colony of bacteria doubles in size every hour. If the colony has 100 bacteria at noon, how many bacteria will it have at 3 pm?

Answer: 800

Three doublings: 100 × 2 × 2 × 2 = 800.

Common wrong answers

If you answered 300
300 adds 100 each hour.
If you answered 400
400 doubles only twice.
If you answered 600
600 adds 200 three times.

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