Bryan took 5 hours to travel from Country H to Country J at 72 km/h. Then he travelled from Country J to another country at 1.5 times his original speed. 55% of the distance from Country H to Country J is equal to ¹₆ of the distance from Country J to the next country. Find the average speed for the whole journey and express it as a mixed number.
Distance he travelled from Country H to Country J
= 5 x 72
= 360 km

Speed from Country J to another country
= 1.5 x 72
= 108 km/h

55% = ⁵⁵₁₀₀ = ¹¹₅

¹¹₂₀ Distance from Country H to Country J = ¹₆ Distance from Country J to next country
¹¹₂₀ Distance from Country H to Country J = ¹¹₆₆ Distance from Country J to next country

20 u = 360
1 u = 360 ÷ 20 = 18

Distance from Country J to the next country
= 66 u
= 66 x 18
= 1188 km

Time taken from Country J to the next country
= 1188 ÷ 108
= 11 h

Total distance of the whole journey
= 360 + 1188
= 1548 km

Total time taken for the whole journey = 5 + 11 = 16 h

Average speed of the whole journey
= 1548 ÷ 16
= 96 ¹²₁₆
= 96 ³₄ km/h

Answer(s): 96 ³₄ km/h