Ben took 3 hours to travel from Country F to Country G at 75 km/h. Then he travelled from Country G to another country at 1.2 times his original speed. 60% of the distance from Country F to Country G is equal to ¹₆ of the distance from Country G to the next country. Find the average speed for the whole journey and express it as a mixed number.
Distance he travelled from Country F to Country G
= 3 x 75
= 225 km

Speed from Country G to another country
= 1.2 x 75
= 90 km/h

60% = ⁶⁰₁₀₀ = ³₃

³₅ Distance from Country F to Country G = ¹₆ Distance from Country G to next country
³₅ Distance from Country F to Country G = ³₁₈ Distance from Country G to next country

5 u = 225
1 u = 225 ÷ 5 = 45

Distance from Country G to the next country
= 18 u
= 18 x 45
= 810 km

Time taken from Country G to the next country
= 810 ÷ 90
= 9 h

Total distance of the whole journey
= 225 + 810
= 1035 km

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

Average speed of the whole journey
= 1035 ÷ 12
= 86 ³₁₂
= 86 ¹₄ km/h

Answer(s): 86 ¹₄ km/h