Question 1173562
Karen's rate,  {{{2/c}}}
Crilyn's rate, {{{1/c}}}
The two together,  {{{1/3}}}


{{{2/c+1/c=1/3}}}
-
{{{3/c=1/3}}}
{{{c/3=3}}}
{{{c=9}}}
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9 hours just for Crilyn
4.5 hours just for Karen