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Problem 232

Algebra Difficulty 1.4 Multiple choice CEMC Pascal · Canada · 2026

Max was given bb books. In
March, he read one third of these books. In April, he read 55 more of the books. Max then had 77 books left to read. If Max never read
the same book more than once, what is the value of bb?

Pick one

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Official solutions — 2

Solution 1

In March, Max read 13\frac13
of the bb books, meaning that he had
1−13=231-\dfrac13=\dfrac23 of the bb books, or 23b\dfrac23b books, left to read. In April,
he read 55 more books, thus leaving
23b−5\dfrac23b-5 books left to read. Max
then had 77 books left to read and
so 23b−5=7\dfrac23b-5=7. Solving, we get
23b=12\dfrac23b=12 or 2b=12×32b=12\times3 and so b=362=18b=\dfrac{36}{2}=18.

Solution 2

In March, Max read 13\frac13
of the bb books, meaning that he had
1−13=231-\dfrac13=\dfrac23 of the bb books, or 23b\dfrac23b books, left to read. In April,
he read 55 more books, thus leaving
23b−5\dfrac23b-5 books left to
read.

Max then had 77 books left to read
and so 23b−5=7\dfrac23b-5=7.

Solving, we get 23b=12\dfrac23b=12 or
2b=12×32b=12\times3 and so b=362=18b=\dfrac{36}{2}=18.

Source: CEMC, University of Waterloo, licensed CC-BY-NC-4.0. Statement reproduced verbatim; metadata (topic, difficulty, ordering) added by this project.