City Q and City R is 420 km apart. Rael left City Q for City R at 10.00 a.m. travelling at an average speed of 70 km/h. Jenson left City Q later than Rael and caught up with him at 2.00 p.m. Jenson was travelling at a speed of 96 km/h.

1. At what time did Jenson leave City Q?
2. How much later did Rael arrive in City R than Jenson? Express your answer in h as a fraction or mixed number.

(a)
From 10.00 a.m. to 2.00 p.m. = 4 h

Distance that Rael covered when Jenson caught up with Rael
= 4 x 70
= 280 km

Time that Jenson took to travel 280 km
= 280 ÷ 96
= 2¹¹₁₂ h

1 h = 60 min
¹¹₁₂ h = ¹¹₁₂ x 60 = 55 min
2¹¹₁₂ h = 2 h 55 min

Time that Jenson left City Q:
2 h 55 min before 2.00 p.m. = 11.05 a.m.

(b)
Remaining distance that they had to cover to reach City R
= 420 - 280
= 140 km

Duration that Jenson had to travel before reaching City R
= 140 ÷ 96
= 1¹¹₂₄ h

Duration that Rael had to travel before reaching City R
= 140 ÷ 70
= 2 h

Duration that Rael took to arrive later than Jenson in City R
= 2 - 1¹¹₂₄
= ¹³₂₄ h

Answer(s): (a) 11.05 a.m.; (b) ¹³₂₄ h