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It took Christine the same time to travel 10km at x km/h as it did to travel 15 km at a speed of 3 km/h faster. Find x

User Bitscuit
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1 Answer

4 votes
Time = Distance/Speed

10/x = 15/(x+3) . . . . . times at the two (distance, speed) pairs are the same

Multiplying by x(x+3), we have
10(x+3) = 15x
30 = 5x
6 = x
User Fernando Castilla
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