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, 2026

Algebra Difficulty 1.2 Junior Find the answer Canada

Jin has $40$ cupcakes, $75\%$ of which are chocolate, and the rest
of which are vanilla. If Jin wants to bake more vanilla cupcakes so that
half of the cupcakes are vanilla and half are chocolate, how many more
vanilla cupcakes should Jin bake?

Pick one

Solution

Of Jin’s $40$ cupcakes, 75% or
$\dfrac34$ are chocolate, and so Jin
has $40\times\dfrac34=30$ chocolate
cupcakes and $40-30=10$ vanilla
cupcakes.

Since Jin has $30-10=20$ more
chocolate cupcakes than she has vanilla cupcakes, then Jin must bake
$20$ more vanilla cupcakes so that
half of the cupcakes are vanilla.

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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.