A and B start from the same point on the same route. A starts at 8 a.m. at 40 kmph and B starts at 9 a.m. at 50 kmph. If the destination is 350 km away, how far will A be from the destination when B reaches it?

A is 30 km short of the destination.

B needs 350 / 50 = 7 hours to cover 350 km.

A started 1 hour earlier, so A travels for 7 + 1 = 8 hours.

A covers 40 x 8 = 320 km in that time.

Distance left for A = 350 - 320 = 30 km.