Question

A and B travel from place P to place Q following the same route in their respective cars. A drives at 60 kmph while B drives at 90 kmph. Find the time taken by B to reach place Q, if A takes 12 hrs.

• A. 10 hrs
• B. 2 hrs
• C. 8 hrs
• D. 4.6 hrs

Hint:

When distance is constant, time is inversely proportional to speed (\(T \propto 1/S\)). The ratio of speeds A:B is 60:90 or 2:3. Therefore, the ratio of times taken will be the inverse, 3:2. If A's time (3 parts) is 12 hours, then 1 part is 4 hours, so B's time (2 parts) is \(2 \times 4 = 8\) hours.

Answer 1

The Correct Option is C

Step 1: Determine the distance between P and Q using A's data.Distance calculation: Distance = Speed × Time.Distance = \( 60 \, \text{km/h} \times 12 \, \text{h} = 720 \, \text{km} \).

Step 2: Calculate B's travel time for the same distance.Time calculation: Time = Distance / Speed.Time for B = \( \frac{720 \, \text{km}}{90 \, \text{km/h}} = 8 \, \text{h} \).