Pierre left City C for City B at 09 30. Usha left City C for City C at the same time. At 12 30, they were 624 km apart. Both maintained a constant speed and reached their destination at the same time at 15 15.
- Find the distance between Cities A and C.
- If Usha was 79 the speed of Pierre, find Pierre's speed.
(a)
Time taken for Pierre and Usha to travel 09 30 to 12 30 = 3 h
Time taken for Pierre and Usha to travel 09 30 to 15 15 = 5 h 45 min = 5
4560 h = 5
34 h
Distance travelled by Pierre and Usha in 1 hour
= 624 ÷ 3
= 208 km
Total distance
= 5
34 x 208
= 1196 km
(b)
Usha's distance : Pierre's distance
7 : 9
Usha's speed : Pierre's speed
7 : 9
16 u = 208 km
1 u = 208 ÷ 16 = 13 km
Pierre's speed
= 9 u
= 9 x 13
= 117 km/h
Answer(s): (a) 1196 km; (b) 117km/h