Question 896291
rate per tap * number of taps * time = quantity of work produced.


let R = rate per tap 
let N = number of taps
let T = time
let Q = quantity of work produced


the formula becomes:


R*N*T = Q


replace N with 4 and T with 5 and Q with 5 and you get:


R*4*5 = 5


solve for R to get:


R = 5/(4*5) = 1/4


each tap can fill 1/4 of a drum in one hour.


4 taps can therefore fill 1 drum in one hour.


4 taps can therefore fill 5 drums in 5 hours.


the formula looks good and the rate per tap is equal to 1/4 of a drum per hour.


now you want to know how many drums can be filled by 10 taps in 6 hours.


the same formula applies:


R*N*T = Q


R = 1/4
N = 10
T = 6
Q will be equal to  1/4 * 10 * 6 = 15 drums.


that's your solution.


15 drums can be filled by 10 taps in 6 hours.


each tap can fill 1/4 of a drum per hour.


that means that 10 taps can fill 10/4 drums per hour.


multiply 10/4 by 6 and you get 60/4 which is equal to 15 drums in 6 hours.