A cat leaps 5 leaps for every 4 leaps of a dog, but 3 leaps of the dog are equal to 4 leaps of the cat. What is the ratio of the speed of the cat to that of the dog?

Answer: Option D

Given;
3dog = 4 cat
Or, $$\frac{\text{dog}}{\text{cat}}=\frac{4}{3}$$
Let cat's 1 leap = 3 meter and dogs 1 leap = 4 meter
Then, ratio of speed of cat and dog = $$\frac{3\times 5}{4\times 4}$$  = 15 : 16