At 11.55 a.m., Perry started driving from Town Q to Town R which was 500 km away. For the first 210 km, he travelled at an average speed of 70 km/h. He then decreased his speed by 10 km/h and completed the remaining journey.
- Find the total time taken for the whole journey. Express your answer as a mixed number.
- At what time did she reach Town R?
(a)
Time taken for the first 210 km
= 210 ÷ 70
= 3/1
= 3 h
Speed for the remaining journey
= 70 - 10
= 60 km/h
Remaining distance
= 500 - 210
= 290 km
Time taken for the remaining journey
= 290 ÷ 60
= 4
5060= 4
56 h
Total time taken
= 3 + 4
56= 3/1 + 4
56= 7
56 h
(b)
1 h = 60 min
56 h =
56 x 60 = 50 min
7 h 50 min after 11.55 a.m. = 7.45 p.m.
Answer(s): (a) 77
56 h; (b) 7.45 p.m.