Kitty Town and Melody Town are 234 km apart. Danny left Kitty Town for Melody Town at 8.42 a.m. travelling at an average speed of 85 km/h. At the same time, Jasmine left Melody Town for Kitty Town. They met each other at 10.30 a.m. (a) What was Jasmine’s average speed when she met Danny? (b) If Jasmine were to increase her speed by 26 km/h before meeting Danny, how much less time would she take before meeting him? [4 marks][Answer given: 45 km/h, 18 min
1 h 18 min 30 min
|--------------------|--------------|---------------|
8.42 am 9.42 am 10 am 10.30 am
1 h 48 min = 1.8 h
234/ 1.8 = 234 x 5/9
= 130 km/h
130 - 85 = 45 km/h
a) It was 45 km/h.
45 + 26 = 71 km/h
71 + 85 = 156 km/h
234/156 = 1.5 h
1.8 - 1.5 = 0.3 h
= 0.3 x 60 min
= 18 min
b) It was 18 min.
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