City F and City G are 504 km apart. At 2.15 p.m., Ryan is travelling at a uniform speed left City F for City G while Elijah set off from City G to City F along the same road at a uniform speed, which was 6 km/h slower than that of Ryan. The two met at 5.15 p.m.

1. Find the speed of Ryan.
2. If Elijah 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 Ryan and Elijah to travel from 2.15 p.m. to 5.15 p.m. = 3 h

Average speed of Ryan and Elijah
= 504 ÷ 3
= 168 km/h

Ryan's speed
= (168 + 6) ÷ 2
= 174 ÷ 2 
= 87 km/h

(b)
Elijah's speed
= 87 - 6
= 81 km/h

Distance that Elijah travelled in 3 h
= 3 x 81
= 243 km

Remaining distance that Elijah needed to travel
= 504 - 243
= 261 km

Time that Elijah needed to reach his destination after the two met
= 261 ÷ 81
= 3¹⁸₈₁
= 3²₉ h

Answer(s): (a) 87 km/h; (b) 3²₉ h