Question 1015578
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A passenger trains speed is 60 mi/h, and a freight trains speed is 40 mi/h. The passenger train travels the same distance in 1.5 h less time than the freight train. How long does each train take to make a trip?
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Let L be the travel distance (now unknown).

Then the passenger train spends {{{L/60}}} hours to cover this distance, while
the freight train spends {{{L/40}}} hours.

According to the condition, the difference of these times is 1.5 hour. It gives you an equation

{{{L/40}}} - {{{L/60}}} = 1.5.

Multiply both sides by 40*60 to get off denominators. You will get

60*L - 40*L = 40*60*1.5,   or

20*L = 3600.

Hence, L = {{{3600/20}}} = 180 km.

Then the passenger train spends {{{180/60}}} = 3 hours, while the greight train spends {{{180/40}}} = 4.5 hours.

The problem is solved.
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