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CEMC Gauss (Grade 8), 2017

Algebra Difficulty 1.4 Junior Find the answer Canada

The volume of the rectangular prism shown is 60 cm $^3$ .

What is the value of $x$ ?

Pick one

Solution

The denominators of the two fractions are 7 and 63.

Since $7\times9=63$ , then we must also multiply the numerator 3 by 9 so that the fractions are equivalent.

That is, $\dfrac37=\dfrac{3\times9}{7\times9}=\dfrac{27}{63}$ .

Therefore, the number that goes into the $\Box$ so that the statement true is 27.

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