A train covers a certain distance in 1 hour 45 minutes and another train covers twice the distance travelled by the first train in 2 hours 45 minutes. What is the ratio of their speeds?
11 : 14
Speed = Distance ÷ Time. Let the first train cover distance d.
Speed of first train = d ÷ (7/4) = 4d/7
Speed of second train = 2d ÷ (11/4) = 8d/11
Ratio = (4d/7) : (8d/11)
= 4/7 : 8/11
= 44 : 56
= 11 : 14
Check: With d = 77 km, speeds are 44 km/h and 56 km/h, and 44 : 56 = 11 : 14.
Hence, 11 : 14.
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