After cycling for 30 km, Warren took a break before he continued cycling ¹₅ of the remaining distance. He then realised that he still had ¹₅ of the total distance not completed. If Warren's average speed was 18 km/h, how much time did he take to complete the entire ride? Express your answer in mixed number.
Fraction of the remaining distance to cycle after resting
= 1 - ¹₅ 
= ⁴₅

⁴₅ of the remaining distance = ¹₅ of the total distance
⁴₅ of the remaining distance = ⁴₂₀ of the total distance

Total distance = 20 u

20 u - 4 u = 1 u + 30
16 u - 1 u = 30
15 u = 30
1 u = 30 ÷ 15 = 2

Total distance
= 20 x 2
= 40 km

Time taken by Warren to travel the entire distance
= 40 ÷ 18
= 2 ⁴₁₈
= 2²₉ h

Answer(s): 2²₉ h