Question

Two bikers A and B start at same time with speeds of 85 km/hr and 80 km/hr respectively. If they both meet after 20 minutes, then what is the distance between them before starting?

• A. 55 km
• B. 15 km
• C. 100 km
• D. 60 km

Answer 1

The correct option is A 55 km

Let the initial distance between the bikers be 'd' km.
Since bikers are travelling in opposite direction to each other, the relative speed of bikers = 85 + 80 = 165 km/hr

Time travelled before meeting each other = 20 minutes = $\frac{20}{60}=\frac{1}{3}hour$
Distance between bikers, d = Relative Speed × Time = $165\times \frac{1}{3}=55km$