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Dana enters a race where she has to cycle and run. She cycles a distance of 25km and then runs for 20km. Her average running speed is half of her average cycling speed. If dana completes the race in 5 hours, what is her average cycling speed !

User Evil
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1 Answer

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Explanation:

Let running speed = x.

So, cycling speed = 2x.

Total distance traveled = 20 + 25 = 45km

Time taken running = 20/x

Time taken cycling = 25/2c

Total time taken = 5 hours

So, 5 = 20/x + 25/2x

Solving this equation for x gives:

10x = 65. Thus x = 6.5

Since cycling speed = 2x, cycling speed = (6.5)(2)

So cycling speed is 13 km/h.

Hope it helps.

User Algorias
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