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CEMC Gauss (Grade 8), 2013

Algebra Difficulty 1.2 Junior Find the answer Canada

What number goes in the box so that $10 \times 20 \times 30 \times 40 \times 50 = 100 \times 2 \times 300 \times 4 \times \Box$ ?

Pick one

Solution

Nick has 6 nickels and each nickel is worth 5¢. So Nick has $6 \times 5$ ¢ or 30¢ in nickels.

Nick has 2 dimes and each dime is worth 10¢. So Nick has $2 \times 10$ ¢ or 20¢ in dimes.

Nick has 1 quarter and each quarter is worth 25¢. So Nick has $1 \times 25$ ¢ or 25¢ in quarters.
In total, Nick has 30¢ $+\,20$ ¢ $+\,25$ ¢ or 75¢.

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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.