Question 705229
A  tap  fills  a  tank 12  hours other  emptied  it in 14  hour if  both are  open how  much will take  time  to fill it..
.
Let x = time (hours) it takes to fill tank
then
x(1/12 - 1/14) = 1
multiplying both sides by (12)(14):
x(14 - 12) = (12)(14)
x(2) = 168
x = 84 hours