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CEMC Gauss (Grade 7), 2019

Algebra Difficulty 1.3 Junior Find the answer Canada

Joshua is reading a 396-page book. He has read the first third of the book only. How many pages does he have left to read to finish the rest of the book?

Pick one

Solution

Solution 1

One third of 396 is $396\div3=132$ . Thus, Joshua has read 132 pages of the book.

To finish the book, Joshua has $396-132=264$ pages left to read.

Solution 2

Joshua has read the first third of the book only, and so he has $1-\frac13=\frac23$ of the book left to read.

Two thirds of 396 is $396\times\frac23=\frac{396\times2}{3}=\frac{792}{3}=264$ .

Joshua has 264 pages left to read.

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