Diana and Ahmad started off from the same place and drove at uniform speeds in the same direction round a 45 km circular racing track. Diana completed each round in 50 minutes. Ahmad took 100 minutes to complete each round.
- How far would Ahmad be behind Diana after 1 hour?
- How long after they started would it take Diana to meet Ahmad for the first time? Express your answer as a whole or mixed number in h.
(a)
60 min = 1 h
1 min =
160 h
50 min =
5060 h =
56 h
100 min =
10060 h = 1
23 h
Diana's speed
= 45 ÷
56= 45 x
65= 54 km/h
Ahmad's speed
= 45 ÷ 1
23= 45 x
35= 27 km/h
Distance between Diana and Ahmad after 1 hour
= 54 - 27
= 27 km
(b)
LCM of 50 and 100 = 100
100 min =
10060 h = 1
23 h
Time needed for Diana to meet Ahmad for the first time = 1
23 h
Answer(s): (a) 27 km; (b) 1
23 h