Maths Olympiad Prep

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, 2014

Algebra Difficulty 1.7 Junior Find the answer Canada

A bicycle at Store P costs $200. The regular price of the same bicycle at Store Q is 15% more than it is at Store P. The bicycle is on sale at Store Q for 10% off of the regular price. What is the sale price of the bicycle at Store Q?

Pick one

Solutions — 2

Solution 1

At Store Q, the bicycle’s regular price is 15%15\% more than the price at Store P, or 15%15\% more than $200.

Since 15%15\% of 200 is 15100×200=0.15×200=30\frac{15}{100}\times200=0.15\times200=30, then 15%15\% more than $200 is $200+$30\$200+\$30 or $230\$230.

This bicycle is on sale at Store Q for 10% off of the regular price, $230.

Since 10%10\% of 230 is 10100×230=0.10×230=23\frac{10}{100}\times230=0.10\times230=23, then 10%10\% off of $230 is $230−$23\$230-\$23 or $207\$207.
The sale price of the bicycle at Store Q is $207.

Solution 2

The width of Sarah’s rectangular floor is 18 hand lengths.

Since each hand length is 20 cm, then the width of the floor is 18×20=36018\times20=360 cm.

The length of Sarah’s rectangular floor is 22 hand lengths.

Since each hand length is 20 cm, then the length of the floor is 22×20=44022\times20=440 cm.

Thus the area of the floor is 360×440=158 400360\times440=158\,400 cm2^2.
Of the given answers, the closest to the area of the floor is 160 000160\,000 cm2^2.

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