Maths Olympiad Prep

Track / Stage 1 / 192 of 240 #192 of 2444

Problem 192

Algebra Difficulty 1.7 Multiple choice CEMC Gauss (Grade 8) · Canada · 2014

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

Next problem →

Official 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 200is200 is \$200+\$30or  or \$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 230is230 is \$230-\$23or or \$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=158400360\times440=158\,400 cm2^2.
Of the given answers, the closest to the area of the floor is 160000160\,000 cm2^2.

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