SOLUTION: substitute several sets of values for two of t, s, and T variables and solve the equation for the third variable. 1) Steve takes 12 hours to finish painting a fence and Janet ta

Algebra ->  Rate-of-work-word-problems -> SOLUTION: substitute several sets of values for two of t, s, and T variables and solve the equation for the third variable. 1) Steve takes 12 hours to finish painting a fence and Janet ta      Log On


   



Question 821526: substitute several sets of values for two of t, s, and T variables and solve the equation for the third variable.
1) Steve takes 12 hours to finish painting a fence and Janet takes 9 hours to finish painting the same fence. How long would it take if they painted the fence together?

Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
1/12+1/9=1/x
9/108+12/108=1/x
21/108=1/x
108/21=x
3*36/3*7=x
36/7=x
5 1/7=x