City M and City N are 484 km apart. At 5.21 p.m., Tim is travelling at a uniform speed left City M for City N while Dylan set off from City N to City M along the same road at a uniform speed, which was 11 km/h slower than that of Tim. The two met at 9.21 p.m.

1. Find the speed of Tim.
2. If Dylan continued to travel at the same speed, how long would it take for him to reach his destination after the two met? Express your answer in mixed number.

(a)
Time taken for Tim and Dylan to travel from 5.21 p.m. to 9.21 p.m. = 4 h

Average speed of Tim and Dylan
= 484 ÷ 4
= 121 km/h

Tim's speed
= (121 + 11) ÷ 2
= 132 ÷ 2 
= 66 km/h

(b)
Dylan's speed
= 66 - 11
= 55 km/h

Distance that Dylan travelled in 4 h
= 4 x 55
= 220 km

Remaining distance that Dylan needed to travel
= 484 - 220
= 264 km

Time that Dylan needed to reach his destination after the two met
= 264 ÷ 55
= 4⁴⁴₅₅
= 4⁴₅ h

Answer(s): (a) 66 km/h; (b) 4⁴₅ h