Now lets solve this question using this approach
You would have observed the following in the question ratio of the speeds are given distance is constant
The relationship between speed and time is : Speed is inversely proportional to time.
Hence if speed increases time decreases and vice versa.
The speeds are in the ratio 3:4:5.
Hence the times should be in the ratio: 1/3 :1/4: 1/5 as speed is inversely proportional to time.
Multiplying with LCM (4,3,5) i.e. 60 …………..to normalize the ratio
We get 20: 15:12
The answer is 20:15:12
Take-away:
Always observe the hidden relationship between numbers
Hope you understood both the methods.
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