Question 1068121
By checking work records, a carpenter finds that Jane can build a small shed in 12 hours. Antoine can do the same job in 16 hours. How long would it take if they worked together? 
------
Let "together" time be x hr/job
Invert that to get rate = (1/x) job/hr
-------------------------
Equation:
rate + rate = together rate
1/12 + 1/16 = 1/x
16x + 12x = 12*16
28x = 192
x = 6.86 hrs = 6hrs 51 min 36 sec
------------
Cheers,
Stan H.
------------------