Mrs Neo left home at 8 a.m. and drove towards the city. 1³₄ hour later, Mr Neo left the house and drove at an average speed of 92 km/h towards the city. When Mr Neo reached his destination at 1 p.m., Mrs Neo was 13 km away from the city. Find Mrs Neo’s average speed in km/h. Express your answer in mixed number.
1 h = 60 min 
³₄ h = ³₄ x 60 = 45 min
1³₄ = 1 h 45 min

1 h 45 min after 8 a.m. = 9.45 a.m.

Time that Mr Neo left the house = 9.45 a.m.

Time that Mr Neo took from 9.45 a.m. to 1 p.m. to reach his destination = 3 h 15 min

1 min = ¹₆₀ h
15 min = ¹⁵₆₀ h = ¹₄ h
3 h 15 min = 3¹₄ h

Distance that Mr Neo drove
= 3¹₄ x 92
= 299 km

Distance that Mrs Neo drove when Mr Neo reached
= 299 - 13 
= 286 km

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

Mrs Neo's average speed
= 286 ÷ 5
= 57¹₅ km/h

Answer(s): 57¹₅ km/h