CAT 2025 Slot 3 QA Question 16: Rahul starts on his journey at 5 pm at a constant speed so that he reaches his destination at 11 pm the same day. However, on his way, he stops for 20 minutes, and after that, increases his speed by 3

Question

Rahul starts on his journey at 5 pm at a constant speed so that he reaches his destination at 11 pm the same day. However, on his way, he stops for 20 minutes, and after that, increases his speed by 3

Accepted Answer

The planned travel time is $6$ hours. Let Rahul’s initial speed be $v$ km/h. Suppose after he stops, the remaining planned travel time is $T$ hours.
With a $20$-minute stop, the remaining travel time becomes $T - \dfrac{1}{3}$ hours, and the new speed is $v+3$.
$vT = (v + 3)(T - \dfrac{1}{3})$
$v =