Question

The sum of the speeds of two trains is 723.1 miles per hour. If the speed of the first train is 10.9 mph faster than that of the second train, find the speeds of each.
What is the speed of the first train?

Answer 1

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Answer:

  367 miles per hour

Step-by-step explanation:

The speed of the faster train is half the total plus half the difference:

  s1 = (723.1 +10.9)/2 = 367 . . . . miles per hour

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Check

The slower train is 367-10.9 = 356.1, and the total is 723.1 mph, as required.

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If you want an equation, you can let x represent the faster speed. Then the total is ...

  x + (x -10.9) = 723.1

  2x = 723.1 +10.9

  x = (723.1 +10.9)/2 = 367