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Algebra Difficulty 1.3 Junior Find the answer Canada

A package of 8 greeting cards comes with 10 envelopes. Kirra has
7 cards but no envelopes. What is the smallest number of packages that
Kirra needs to buy to have more envelopes than cards?

Pick one

Solution

When Emily jumps for 75 seconds, she jumps for $60+15$ seconds.

Jumping at the rate of 52 times in 60 seconds, Emily jumps $52\div4=13$ timesin $60\div4=15$ seconds.

Since Emily jumps 52 times in 60 seconds and 13 times in 15 seconds,
then Emily jumps $52+13=65$ times in
$60+15=75$ seconds.

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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.