Worksheet 9 Challenge Yourself Qs 3 (Charmaine and Jie Yi)

A and B are at the starting and finishing points respectively of a 12-km cross-country route.
At 0700, Chad jogs from A towards B at 6km/h.
At 0730, Wei Liang jogs from B towards A at 3km/h.
(i) What time will Chad and Wei Liang meet?
(ii) How far would Chad have jogged when he meets Wei Liang?

Let the distance of 12-km be "a".

Chad 0700 - 0730:
T –> 0.5h
S –> 6km/h
D –> 0.5 x 3 = 3km

Distance between Chad and Wei Liang at 0730 –> (a - 3)km
Total speed of Chad and Wei Liang –> 6km/h + 3km/h = 9km/h
Time taken to meet –> (a-3)/9 h

Find "a":
a -3 / 9
a = 9+3
a = 12

Time taken to meet –> (12-3)/9 = 9/9 = 1h
0730 –1hour–> 0830

Distance Chad jogged:
T –> 0.5 + 1 = 1.5h
Speed –> 6km/h
Distance –> 1.5 x 6 = 9km

(i) Chad will meet Wei Liang at 0830
(ii) Chad would have jogged 9km when he met Wei Liang.