Michael took 6 hours to travel from Country L to Country M at 55 km/h. Then he travelled from Country M to another country at 1.2 times his original speed. 30% of the distance from Country L to Country M is equal to ¹₆ of the distance from Country M to the next country. Find the average speed for the whole journey and express it as a mixed number.
Distance he travelled from Country L to Country M
= 6 x 55
= 330 km

Speed from Country M to another country
= 1.2 x 55
= 66 km/h

30% = ³⁰₁₀₀ = ³₆

³₁₀ Distance from Country L to Country M = ¹₆ Distance from Country M to next country
³₁₀ Distance from Country L to Country M = ³₁₈ Distance from Country M to next country

10 u = 330
1 u = 330 ÷ 10 = 33

Distance from Country M to the next country
= 18 u
= 18 x 33
= 594 km

Time taken from Country M to the next country
= 594 ÷ 66
= 9 h

Total distance of the whole journey
= 330 + 594
= 924 km

Total time taken for the whole journey = 6 + 9 = 15 h

Average speed of the whole journey
= 924 ÷ 15
= 61 ⁹₁₅
= 61 ³₅ km/h

Answer(s): 61 ³₅ km/h