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Algebra Difficulty 2.5 Junior Find the answer Canada

Anca and Bruce left Mathville at the same time. They drove along a straight highway towards Staton.

Bruce drove at 50 km/h. Anca drove at 60 km/h, but stopped along the way to rest. They both arrived at Staton at the same time. For how long did Anca stop to rest?

Pick one

Solutions — 2

Solution 1

Since Bruce drove 200 km at a speed of 50 km/h, this took him $\frac{200}{50} = 4$ hours.

Anca drove the same 200 km at a speed of 60 km/h with a stop somewhere along the way.

Since Anca drove 200 km at a speed of 60 km/h, the time that the driving portion of her trip took was $\frac{200}{60}=3\frac{1}{3}$ hours.

The length of Anca’s stop is the difference in driving times, or $4 - 3\frac{1}{3}=\frac{2}{3}$ hours.

Since $\frac{2}{3}$ hours equals 40 minutes, then Anca stops for 40 minutes.

Solution 2

Since Bruce drove 200 km at a speed of 50 km/h, this took him $\frac{200}{50} = 4$ hours.

Anca drove the same 200 km at a speed of 60 km/h with a stop somewhere along the way.

Since Anca drove 200 km at a speed of 60 km/h, the time that the driving portion of her trip took was $\frac{200}{60}=3\frac{1}{3}$ hours.

The length of Anca’s stop is the difference in driving times, or $4 - 3\frac{1}{3}=\frac{2}{3}$ hours.

Since $\frac{2}{3}$ hours equals 40 minutes, then Anca stopped for 40 minutes.

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