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Algebra Difficulty 1.3 Junior Find the answer Canada

A bicycle trip is 30 km long. Ari rides at an average speed of 20
km/h. Bri rides at an average speed of 15 km/h. If Ari and Bri begin at
the same time, how many minutes after Ari finishes the trip will Bri
finish?

Pick one

Solution

Riding at 15 km/h, Bri finishes the 30 km in $\$\dfrac{30\text{ km}}{15\text{}}$ km/h}} = $2\text{}$
h}$.

Riding at 20 km/h, Ari finishes the 30 km in $\$\dfrac{30\text{ km}}{20\text{}}$ km/h}} = $1.5\text{}$
h}$.

Therefore, Bri finishes 0.5 h after Ari, which is 30 minutes.

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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.