Difficulty: Tricky

Lisa had a difficult time falling asleep on Wednesday night, so she began counting sheep. She counted 56 sheep before falling asleep. On Thursday, she had to count twice the number of sheep she counted on Wednesday night before she fell asleep. On Friday, she counted sheep to help her sleep again.

How many sheep did Lisa count on Friday if she counted 178 sheep in total?

Scroll down or click for a hint, or the answer!


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Brainteaser hint

Think about how many sheep Lisa counted on Friday and figure out what’s missing!

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Brainteaser answer

On Wednesday, Lisa counted 56 sheep.

On Thursday, Lisa counted twice as many sheep compared to Wednesday, which is 56 x 2 = 112.

We know that over the 3 nights she counted 178 sheep in total. And over the first 2 nights she counted 56 + 112 = 168 sheep

This means that Lisa would have counted 178 – 168 = 10 sheep on Friday. Hooray for the weekend!

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