1.  A person has to cover a distance of 6 km in 45 minutes. If he cover one-half of the distance in two-thirds of the total time; to cover the remaining distance in the remaining time, his speed (in km/hr) must be :
A. 6
B. 8
C. 12
D. 15

Answer: Option C

Explanation:

Remaining distance = 3 km
Remaining time = (1/3 x 45) min
                       = 15 min
                       = 1/4 hour.

∴ Required speed = (3 x 4) km / hr = 12 km / hr