Question 1155702
Sue can do an inventory by herself in 6 hours.
 Sue and Ann work together on the inventory for 3 hours.
 Then Ann finishes up the job by herself in 2 additional hours.
 How many hours would it take Ann to do the entire inventory if she worked alone?
:
let a = time required by Ann working alone
let the completed job = 1
"Sue and Ann work together on the inventory for 3 hours. Then Ann finishes up the job by herself in 2 additional hours."
Sue works a total of 5 hrs, Ann works 3
{{{5/6}}} + {{{3/a}}} = 1
Multiply equation by 6a
5a + 6(3) = 6a
18 = 6a - 5a
18 = a
Ann required 18 hrs to do the job alone
:
:
See if that checks out
{{{5/6}}} + {{{3/18}}} = 1
{{{5/6}}} + {{{1/6}}} = 1