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Geometry Difficulty 1.5 Junior Find the answer Canada

Rectangle $ABCD$ has side length $AB=16$ m and diagonal length $AC=34$ m, as shown.The perimeter of rectangle $ABCD$ is

Pick one

Solution

Before Jack eats any jelly beans, the box contains $15+20+16=51$ jelly beans. After Jack eats 2 jelly beans, there are $51-2=49$ jelly beans remaining in the box. One of the jelly beans that Jack ate was green, and the other was blue. Thus after eating the 2 jelly beans, there are still 15 red jelly beans in the box. If each of the remaining jelly beans is equally likely to be chosen, the probability that Jack chooses a red jelly bean next is $\frac{15}{49}$ .

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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.