Question

The ratio of speeds of A and B is 3:4. If A takes 40 minutes to cover a distance, how much time will B take for the same distance?

• A. 30 minutes
• B. 35 minutes
• C. 45 minutes
• D. 50 minutes

Hint:

For same distance problems, always invert the speed ratio to get the time ratio.

Answer 1

The Correct Option is A

Concept: For the same distance: \[ {Speed} \propto \frac{1}{{Time}} \Rightarrow {Time ratio is inverse of speed ratio} \]
Step 1: Given speed ratio.
\[ A : B = 3 : 4 \]
Step 2: Time ratio (inverse).
\[ T_A : T_B = 4 : 3 \]
Step 3: Find time for B.
\[ T_A = 40 \] \[ T_B = 40 \times \frac{3}{4} = 30 \]
Hence, B will take 30 minutes.