Two cars A and B leave Delhi at 8:30 a.m. and at 9 a.m. for Shimla, respectively. They travel at the speeds of 40 km/h and 50 km/h respectively. How many kilometres away from Delhi will the two cars be together ?

100 km

Relative speed of car ( moves in same direction ) = 50 - 40 = 10 km/h

Distance  = Speed × Time

Distance traveled by first car in half an hour = 40 × \(\frac{1}{2}\) = 20 km

Both the cars meet in = \(\frac{20}{10}\) = 2 hours

Distance covered by 2nd car to meet 1st car in 2 hours = 50× 2 = 100 km