A boy walks 800m in 20 minutes. Calculate his average speed in km per hour
A
2.4
B
4
C
16
D
24
Verified Correct Answer: A.
Step-by-Step Mathematical Solution
\(Average \hspace{1mm}speed = \frac{Distance}{Time\hspace{1mm} taken}\)
Distance = 800m = \(\frac{800}{1000}\)km = 0.8km
Time\(\hspace{1mm}taken = 20\hspace{1mm}minutes = \frac{20}{60}\)hr
= \(\frac{1}{3}hr\\Average \hspace{1mm} speed = \left(0.8\div \frac{1}{3}\right)\)km/hr
= (0.8\(\times\)3)km/hr =2.4km/hr
Source: Myschool Past Questions Archive (Record #26656)