City J and City K are 396 km apart. At 4.34 p.m., Will is travelling at a uniform speed left City J for City K while Albert set off from City K to City J along the same road at a uniform speed, which was 12 km/h slower than that of Will. The two met at 7.34 p.m.

1. Find the speed of Will.
2. If Albert 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 Will and Albert to travel from 4.34 p.m. to 7.34 p.m. = 3 h

Average speed of Will and Albert
= 396 ÷ 3
= 132 km/h

Will's speed
= (132 + 12) ÷ 2
= 144 ÷ 2 
= 72 km/h

(b)
Albert's speed
= 72 - 12
= 60 km/h

Distance that Albert travelled in 3 h
= 3 x 60
= 180 km

Remaining distance that Albert needed to travel
= 396 - 180
= 216 km

Time that Albert needed to reach his destination after the two met
= 216 ÷ 60
= 3³⁶₆₀
= 3³₅ h

Answer(s): (a) 72 km/h; (b) 3³₅ h