The speed of two cars A & B  is in ratio 3 : 4 . Find ratio of time taken by them .

4 : 3

Distance =  Speed × Time

&  Speed =   \(\frac{Distance}{Time}\)

If distance is same , The ratio of the speeds of two objects is inversely proportional to the ratio of the time by them to cover the same distance.

Ratio of speed of car A & B = 3 : 4

Let speed of car A = 3x & Speed of car B = 4x

And Distance = D

                 A     :      B 

Speed      3      :      4

Time       \(\frac{D}{3x}\)        :       \(\frac{D}{4x}\)

Time       \(\frac{1}{3}\)        :       \(\frac{1}{4}\)

               4      :       3