easymath

In a lake, there is a patch of lily pads. Every day, the patch doubles in size. If it takes 48 days for the patch to cover the entire lake, how long would it take for the patch to cover half the lake?

The patch doubles in size every day and so on the 47th day the patch will be half the size it is on the 48th day

Why this works

This riddle plays with the concept of exponential growth. Since the lily pad patch doubles in size each day, if it completely covers the lake on the 48th day, it must have been half that size the day before, on the 47th day. Thus, the answer is 47 days—it's a clever way to illustrate how quickly things can grow when they double!

Common Wrong Answers

“24 days”

The growth pattern of the lily pads is exponential, not linear. Since the patch doubles in size each day, it would be half the size of the lake one day before it completely covers the lake.

“36 days”

This guess assumes a slower growth rate, but the riddle specifies that the size of the patch doubles every day, meaning the patch would be half the lake one day before it is fully covered.

“48 days”

This answer indicates that the patch would cover half the lake on the same day it covers the entire lake, which contradicts the doubling nature of its growth.

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