Travel by a slow and faster train to same destination

Question

An express train takes 51/2 hours to travel between two cities. If the Express train takes only 3/5 of the time an ordinary train takes, how long will it take for the ordinary train to travel between the two towns?

Thank you for the answer Bob, but how do I set this out as a 'Let' statement?

Answer 1

The express train is faster... it takes only 3/5 of the time an ordinary train takes. Express train time = (3/5) * ordinary train time The express train takes 5 and 1/2 hours, which is the same as 5.5 x 60 = 330 minutes. 330 = (3/5) * ordinary train time Divide both sides of the equation by (3/5), which is the same thing as multiply both sides of the equation by (5/3). (5/3) * 330 = (5/3) * (3/5) * ordinary train time So, 550 = ordinary train time The ordinary train takes 550 minutes, while the express train takes only 3/5 of that time (330 minutes). If you convert the ordinary train time from minutes to hours, 550 minutes * (1 hour/60 minutes) = 9 and 1/6 hours = 9 hours and 10 minutes