Question

Two trains leave the station at the same time, one heading east and the other west. The eastbound train travels 14 miles per hour slower than the westbound train. If the two trains are 540 miles apart after 3 hours, what is the rate of the eastbound train? Do not do any rounding.

Answer 1

83 mph

Explanation:

Their combined speed is 540 mi/(3 h) = 180 mi/h. The eastbound train's speed will be half this, less half the difference: 180/2 - 14/2 = 83 mi/h.

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If s represents the slower train's speed, then ...

s + (s +14) = 180 . . . . the sum of the train speeds is 180 mph

2s + 14 = 180 . . . . . . .simplify

2s = 180 -14 . . . . . . . .subtract 14

s = 180/2 -14/2 = 83 . . . . divide by 2