Two persons C & D started traveling from A and B which are 300 km apart, towards B and A respectively at 1.00 p.m. C travels at a constant speed of 30 kmph whereas D doubles his speed every hour. If D reaches A in 4 5/8 hours, at what time did C and D meet each other ?
12 p.m
5:00 p.m
4:30 p.m
4:40 p.m
Explanation:
Let speed of D in first hour = x
D’s speed = x+ 2x+ 4x+ 8x+ 16x*(5/8) = 25x
Given 25x=300 :. X = 12
At the end of four hours C traveled 120 (30 *4) kmph and D traveled 12 + 24+ 48 +96 = 180kmph
They meet each other after 4 hours ie at 5 p.m.
Let speed of D in first hour = x
D’s speed = x+ 2x+ 4x+ 8x+ 16x*(5/8) = 25x
Given 25x=300 :. X = 12
At the end of four hours C traveled 120 (30 *4) kmph and D traveled 12 + 24+ 48 +96 = 180kmph
They meet each other after 4 hours ie at 5 p.m.