Sam took 5 hours to travel from Country E to Country F at 52 km/h. Then he travelled from Country F to another country at 1.5 times his original speed. 50% of the distance from Country E to Country F is equal to ¹₆ of the distance from Country F to the next country. Find the average speed for the whole journey and express it as a mixed number.
Distance he travelled from Country E to Country F
= 5 x 52
= 260 km

Speed from Country F to another country
= 1.5 x 52
= 78 km/h

50% = ⁵⁰₁₀₀ = ¹₅

¹₂ Distance from Country E to Country F = ¹₆ Distance from Country F to next country
¹₂ Distance from Country E to Country F = ¹₆ Distance from Country F to next country

2 u = 260
1 u = 260 ÷ 2 = 130

Distance from Country F to the next country
= 6 u
= 6 x 130
= 780 km

Time taken from Country F to the next country
= 780 ÷ 78
= 10 h

Total distance of the whole journey
= 260 + 780
= 1040 km

Total time taken for the whole journey = 5 + 10 = 15 h

Average speed of the whole journey
= 1040 ÷ 15
= 69 ⁵₁₅
= 69 ¹₃ km/h

Answer(s): 69 ¹₃ km/h