At 8 a.m., Sam left Hotel J in his car and travelled towards Hotel K at 87 km/h. At the same time, David left Hotel J in his car and travelled in the opposite direction towards Hotel L. When David reached Hotel L at 10.40 a.m., Sam was 10 km away from Hotel K.
- What was the distance from Hotel J to Hotel K?
- If the distance between Hotel K and Hotel L was 450 km, what was David's speed?
(a)
From 8 a.m. to 10.40. am = 2 h 40 min
60 min = 1 h
1 min =
160 h
40 min =
4060 =
23 h
2 h 40 min = 2
23 h
Distance from Hotel J to Hotel K
= 87 x 2
23 + 10
= 87 x
83 + 10
= 232 + 10
= 242 km
(b)
Distance travelled by David
= 450 - 242
= 208 km
David's speed
= 208 ÷ 2
23 = 208 ÷
83 = 208 x
38 = 78 km/h
Answer(s): (a) 242 km; (b) 78 km/h