PSLE
Penny and Ava started jogging from the same point of the 12 km track round a nature reserve. They started at the same time but in opposite directions. Penny jogged past Ava after 10 km. Both of them did not change their speeds throughout. Penny took 15 min to complete one round. What was Ava's jogging speed in m/min?
Distance that Ava jogged when they passed each other
= 12 - 10
= 2 km

Time that Penny took to jog 12 km = 15 min

Time that Penny took to jog 1 km
= 15 ÷ 12
= 1.25 min

Time that Penny took to jog 10 km
= 10 x 1.25
= 12.5 min

When Penny took 12.5 min to jog 10 km, Ava took the same time to jog 2 km.

1 km = 1000 m
2 km = 2000 m

Ava's jogging speed
= 2000 ÷ 12.5
= 160 m/min

Answer(s): 160 m/min