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joja [24]
3 years ago
9

A passenger train travels 392 mi in the same time that it takes a freight train to travel 322 mi. If the passenger train travels

20 mi/h faster than the freight train, find the speed of each train.
Physics
1 answer:
Yuri [45]3 years ago
6 0

Answer:

Explanation:

Given

distance traveled by  Passenger train is d_1=392\ mi

distance traveled by  Freight train is d_2=322\ mi

Both take same time to travel

suppose speed of freight train is x mph

so speed of passenger train is 20+x mph

we know time=\frac{distance}{speed}

t=\frac{392}{20+x}=\frac{322}{x}

392x=322x+322\times 20

70x=322\times 20

x=92\ mph

speed of passenger train x+20=112\ mph  

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