The speed of A and B are in the ratio 3 : 4. A takes 20 minutes more than B to reach a destination. In what time does A reach the destination ?

Answer: Option A

Ratio of speed = 3 : 4
Ratio of time taken = $$\frac{1}{3}$$ : $$\frac{1}{4}$$ = 4 : 3
Let A and B take 4x and 3x minutes respectively to reach a destination.
Then,
⇔ 4x - 3x = 20
⇔ x = 20
∴ Time taken by A
= 4x
= (4 × 20) min
= 80 min
= $$1\frac{1}{3}$$ hours