City B and City C are 576 km apart. At 6.52 p.m., Japheth is travelling at a uniform speed left City B for City C while Perry set off from City C to City B along the same road at a uniform speed, which was 8 km/h slower than that of Japheth. The two met at 10.52 p.m.

1. Find the speed of Japheth.
2. If Perry 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 Japheth and Perry to travel from 6.52 p.m. to 10.52 p.m. = 4 h

Average speed of Japheth and Perry
= 576 ÷ 4
= 144 km/h

Japheth's speed
= (144 + 8) ÷ 2
= 152 ÷ 2 
= 76 km/h

(b)
Perry's speed
= 76 - 8
= 68 km/h

Distance that Perry travelled in 4 h
= 4 x 68
= 272 km

Remaining distance that Perry needed to travel
= 576 - 272
= 304 km

Time that Perry needed to reach his destination after the two met
= 304 ÷ 68
= 4³²₆₈
= 4⁸₁₇ h

Answer(s): (a) 76 km/h; (b) 4⁸₁₇ h