Kylie started jogging from the market to the garden at a speed of 110 m/min at 6 a.m. Her brother started jogging from the market later. They were beside each other at 6.32 a.m. and her brother reached the garden at 7 a.m. while Kylie was still 1400 m away. If both of them travelled at a constant speed throughout the journey, what time did her brother leave the market?
1 h = 60 min

From 6 a.m. to 7 a.m. = 1 h
From 6.32 a.m. to 7 a.m. = 28 min

Distance between the market and the garden
= 60 x 110 + 1400
= 6600 + 1400
= 8000 m

Distance that Kylie's brother had to cover to catch up with Kylie
= 32 x 110
= 3520 m

Distance that Kylie's brother travelled to the garden after catching up with Kylie
= 8000 - 3520
= 4480 m

Since Kylie's brother jogged 4480 m in 32 min,
Kylie's brother average speed
= 4480 ÷ 28
= 160 m/min

Duration that Kylie's brother took to jog to the garden
= 8000 ÷ 160
= 50 min

Time that Kylie's brother left the market:
50 min before 7 a.m. = 6.10 a.m.

Answer(s): 6.10 a.m.