The speed of A and B are in the ratio 3 : 4. A takes 20 minutes more than B to reach a destination. Time in which A reach the destination?
A. $1 \frac{1}{3}$ hours B. 2 hours C. $2 \frac{2}{3}$ hours D. $1 \frac{2}{3}$ hours Answer: Option AShow Answer
Solution(By Apex Team)
Ratio of speed = 3 : 4
Ratio of time taken = 4 : 3 (As Speed ∝ $\frac{1}{\text { Time }}$
When distance remains constant.)
Let time taken by A and B be 4x and 3x hour respectively.
Then,
$\begin{array}{l}
4 x-3 x=\frac{20}{60} \\
\text { Or, } x=\frac{1}{3}
\end{array}$
Hence, time taken by A = 4x hours
=$4 \times \frac{1}{3}=1 \frac{1}{3}$ hours.
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