Question

The speeds of $3$ cars are in the ratio $5 : 4 : 6$. The ratio between the time taken by them to travel same distance is:

Accepted Answer

A. Time is inversely proportional to speed for a constant distance. $$	ext{Ratio of time} = \frac{1}{5} : \frac{1}{4} : \frac{1}{6}$$ LCM of 5, 4, 6 is 60. Multiplying each term by 60: $$= 12 : 15 : 10$$

Ratio of time taken by cars

Explanation

Practise this under exam conditions