Two taps X and Y can fill a tank in 10 hrs. and 15 hrs.respectively. If the both taps are opened together, the tank will be full in_________?
A. 3 hrs.
B. 4 hrs,
C. 5 hrs.
D. 6 hrs.
Correct Answer: D
A. 3 hrs.
B. 4 hrs,
C. 5 hrs.
D. 6 hrs.