City D and City E are 312 km apart. At 1.52 p.m., Howard is travelling at a uniform speed left City D for City E while Andy set off from City E to City D along the same road at a uniform speed, which was 12 km/h slower than that of Howard. The two met at 3.52 p.m.

1. Find the speed of Howard.
2. If Andy 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 Howard and Andy to travel from 1.52 p.m. to 3.52 p.m. = 2 h

Average speed of Howard and Andy
= 312 ÷ 2
= 156 km/h

Howard's speed
= (156 + 12) ÷ 2
= 168 ÷ 2 
= 84 km/h

(b)
Andy's speed
= 84 - 12
= 72 km/h

Distance that Andy travelled in 2 h
= 2 x 72
= 144 km

Remaining distance that Andy needed to travel
= 312 - 144
= 168 km

Time that Andy needed to reach his destination after the two met
= 168 ÷ 72
= 2²⁴₇₂
= 2¹₃ h

Answer(s): (a) 84 km/h; (b) 2¹₃ h