Question 781860
 Shawna can mop a warehouse in 12 hours. Totsakam can mop the same warehouse in 9 hours. If they worked together how long would it take them?
-----
Shawna rate:: 1/12 job/hr
Tot rate::::: 1/9 job/hr
----
Together rate:: 1/x job/hr
------
Equation:
rate + rate = together rate
1/12 + 1/9 = 1/x
9x + 12x = 9*12
21x = 9*12
x = 12/7 = 1 5/7 hours (time to do the job together)
============
Cheers,
Stan H.
=============