Maths Olympiad Prep

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, 2014

Algebra Difficulty 1.2 Junior Find the answer Canada

Meg started with the number 100. She increased this number by 20% and then increased the resulting number by 50%. Her final result was

Pick one

Solution

20% of the number 100 is 20, so when 100 is increased by 20%, it becomes 100+20=120100+20=120.

50% of a number is half of that number, so 50% of 120 is 60.

Thus, when 120 is increased by 50%, it becomes 120+60=180120+60=180.

Therefore, Meg’s final result is 180.

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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.