Correct option is A
L.C.M of 48 and 60 is 120
Total work = 120 unit
Let the total time taken to fill the tank be 'x' min
⇒Q is opened from x/2 min and P is opened for x/2 min
3x/2 + 2x/2 = 120
⇒x= 48 min
Both pipes fill the tank in 48 min.