<PRE><B>Question 449652</B>
Gina and Cal can spray an orchard in 8 hours.
 Gina working alone would take 12 hours to do the job.
 How long would it take Cal working alone to do the job?
:
Let c = time required by Cal alone
:
Let the completed job = 1; (a sprayed orchard)
:
A typical shared work equation
{{{8/12}}} + {{{8/c}}} = 1
Multiply by 12c, results
8c + 8(12) = 12c
96 = 12c - 8c
4c = 96
c = {{{96/4}}}
c = 24 hrs Cal working alone
;
:
See if that flies
8/12 + 8/24 = 
2/3 + 1/3 = 1</PRE>