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Algebra Difficulty 2.5 Junior Find the answer Canada

The height of a stack of identical newspapers is $50~\text{cm}$ . Half of the newspapers are
removed from the stack. Then $\frac{1}{5}$ of those removed are put back
onto the stack. What is the height of the stack now?

Pick one

Solution

Half of the stack, or $\$25\text{}$
cm}, is removed from the stack and so $25\text{}$ cm}$ remains in the stack.

Of the $25\text{ cm}$ removed, $\dfrac15\times 25\text{ cm}=5\text{ cm}$
are put back onto the stack.

The final height of the stack is $\$25\text{ cm}+5\text{ cm}=30\text{}$ cm}$.

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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.