44 pipes can fill a large water tank in 27 hours. How many hours will it take for 66 pipes to fill four such tanks? Options are:- [1] 72 [2] 54 [3] 63 [4] 84

 44 pipes can fill a large water tank in 27 hours. How many hours will it take for 66 pipes to fill four such tanks?
Options are:- 
[1] 72    [2]  54     [3] 63      [4] 84  

Answer :-

[1] 72  

Let it takes x hours for 66 pipes  to fill  one large water tank.
And according to question 44 pipes can fill a large water tank in 27 hours.
Here,
The amount of work is same in each case. that is,
44 pipes times 27 hours = 66 pipes times x hours
Since the value of  x is  = 18 hours 
It means 66 pipes can fill one tank in 18 hours.
Hence, 66 pipes will fill 4 such tanks in 18 times 4 = 72 hours.