Mrs Gan left home at 8 a.m. and drove towards the city. 1¹₄ hour later, Mr Gan left the house and drove at an average speed of 104 km/h towards the city. When Mr Gan reached his destination at 1 p.m., Mrs Gan was 24 km away from the city. Find Mrs Gan’s average speed in km/h. Express your answer in mixed number.
1 h = 60 min 
¹₄ h = ¹₄ x 60 = 15 min
1¹₄ = 1 h 15 min

1 h 15 min after 8 a.m. = 9.15 a.m.

Time that Mr Gan left the house = 9.15 a.m.

Time that Mr Gan took from 9.15 a.m. to 1 p.m. to reach his destination = 3 h 45 min

1 min = ¹₆₀ h
45 min = ⁴⁵₆₀ h = ³₄ h
3 h 45 min = 3³₄ h

Distance that Mr Gan drove
= 3³₄ x 104
= 390 km

Distance that Mrs Gan drove when Mr Gan reached
= 390 - 24 
= 366 km

Time that Mrs Gan took to travel from 8 a.m. to 1 p.m. = 5 h

Mrs Gan's average speed
= 366 ÷ 5
= 73¹₅ km/h

Answer(s): 73¹₅ km/h