The speed of three cars in the ratio 3 : 4 : 5. The ratio between time taken by them to travel the same distance is Pick one:
A) 20 : 15 :92  B) 20 : 15 :19  C) 20 : 15 :29  D) 20 : 15 :11  E) 20 : 15 :12
Let the speeds of cars be 3x, 4x and 5x kmph   Distance travelled by each car be y km   \inline \therefore Ratio of times taken = \inline \frac{y}{3x}:\frac{y}{4x}:\frac{y}{5x}   = \inline \frac{1}{3}:\frac{1}{4}:\frac{1}{5}   = 20 : 15 :12   Answer:20 : 15 :12
<result>E</result>
The speed of three cars in the ratio 3 : 4 : 5. The ratio between time taken by them to travel the same distance is