A woman cycle 30 km in 1 hours 45 minutes. A part of her journey is on a level road 18 km long, and the remaining journey is uphill. If the woman's average speed on the level road is 24 km/h, what is her uphill speed (in km/h)?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is Option 3 i.e. 12.
Total distance = 30 km
Time = 1 hr 45 min = 1.75 hrs
Level road: 18 km at 24 km/h
Time = 18 ÷ 24 = 0.75 hrs
Remaining time = 1.75 − 0.75 =1 hr
Remaining distance (uphill) = 30 − 18 = 12 km
Uphill speed = 12/1 = 12 km/h