City Q and City R are 600 km apart. At 3.37 p.m., Xavier is travelling at a uniform speed left City Q for City R while Ian set off from City R to City Q along the same road at a uniform speed, which was 8 km/h slower than that of Xavier. The two met at 6.37 p.m.

1. Find the speed of Xavier.
2. If Ian 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 Xavier and Ian to travel from 3.37 p.m. to 6.37 p.m. = 3 h

Average speed of Xavier and Ian
= 600 ÷ 3
= 200 km/h

Xavier's speed
= (200 + 8) ÷ 2
= 208 ÷ 2 
= 104 km/h

(b)
Ian's speed
= 104 - 8
= 96 km/h

Distance that Ian travelled in 3 h
= 3 x 96
= 288 km

Remaining distance that Ian needed to travel
= 600 - 288
= 312 km

Time that Ian needed to reach his destination after the two met
= 312 ÷ 96
= 3²⁴₉₆
= 3¹₄ h

Answer(s): (a) 104 km/h; (b) 3¹₄ h