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Algebra Difficulty 1.4 Junior Find the answer Canada

Maria drove $500$ km in $8$ hours. Andrea flew a helicopter $1500$ km and averaged a speed that was
four times Maria's average driving speed. How long did Andrea's flight
take?

Pick one

Solution

Maria drove $500\text{ km}$ in
$8$ hours and thus had an average
speed of $\$\dfrac{500\text{ km}}{8\text{ h}}=62.5\text{}$ km/h}$.

Andrea’s average speed was four times Maria’s, or $\$4\times62.5\text{ km/h}=250\text{}$
km/h}$.

Andrea’s flight was $1500\text{ km}$ ,
and so her flight took $\$\dfrac{1500\text{ km}}{250\text{}}$ km/h}}=6$ hours.

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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.