Question 997068
Jerry can lay a tile floor in 3 hours less time than Jake. If they can work together, the floor takes 2 hours. How long would it take Jerry to lay the floor by himself?
<pre>Let time Jerry takes be J
Then Jerry can do {{{1/J}}} of the floor in 1 hour
Also, time Jake takes = J + 3
Jake can do {{{1/(J + 3)}}} of floor in 1 hour
With them working together, we get: {{{1/J + 1/(J + 3) = 1/2}}}
2(J + 3) + 2J = J(J + 3) ------ Multiplying by LCD, 2J(J + 3) 
{{{2J + 6 + 2J = J^2 + 3J}}}
{{{4J + 6 = J^2 + 3J}}}
{{{J^2 + 3J - 4J - 6 = 0}}}
{{{J^2 - J - 6 = 0}}}
(J - 3)(J + 2) = 0
J, or time it takes Jerry, alone = {{{highlight_green(3)}}} hours       OR     J = - 2(ignore)