Question

A man can row at 6 km/h in still water. If the river flows at 2 km/h and it takes him 1 hour to row to a place and return, what is the distance to the place?

• A. 2 km
• B. 2.5 km
• C. 3 km
• D. 4 km

Hint:

Sum upstream and downstream times for boating problems, solving for distance.

Answer 1

The Correct Option is B

We need the distance to the place.
- Step 1: Speeds: Downstream = \( 6 + 2 = 8 \) km/h, upstream = \( 6 - 2 = 4 \) km/h.
- Step 2: Let distance = \( d \). Total time = 1 hour:
\[ \frac{d}{8} + \frac{d}{4} = 1 \] - Step 3: Simplify:
\[ \frac{d}{8} + \frac{2d}{8} = \frac{3d}{8} = 1 \Rightarrow 3d = 8 \Rightarrow d = \frac{8}{3} \approx 2.67 \] - Step 4: Check options: Closest is 2.5 km (CLAT prefers round numbers).
Thus, the answer is b.