A single lily pad doubles in surface area each day, completely blanketing a pond on day 48. If four identical lily pads begin growing simultaneously under the same conditions, on what day will they completely blanket the pond together?
Day 46
Four lily pads provide 4 times the initial coverage, which equals two doublings (2^2 = 4) ahead of a single pad. Therefore, they reach full coverage 2 days earlier than a single pad: 48 - 2 = 46 days.
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Medium. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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