Ryan took 3 hours to travel from Country R to Country S at 55 km/h. Then he travelled from Country S to another country at 1.2 times his original speed. 60% of the distance from Country R to Country S is equal to ¹₆ of the distance from Country S to the next country. Find the average speed for the whole journey and express it as a mixed number.
Distance he travelled from Country R to Country S
= 3 x 55
= 165 km

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

60% = ⁶⁰₁₀₀ = ³₃

³₅ Distance from Country R to Country S = ¹₆ Distance from Country S to next country
³₅ Distance from Country R to Country S = ³₁₈ Distance from Country S to next country

5 u = 165
1 u = 165 ÷ 5 = 33

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

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

Total distance of the whole journey
= 165 + 594
= 759 km

Total time taken for the whole journey = 3 + 9 = 12 h

Average speed of the whole journey
= 759 ÷ 12
= 63 ³₁₂
= 63 ¹₄ km/h

Answer(s): 63 ¹₄ km/h