Question 1134009
Andrea's rate  {{{1/x}}}
Samantha's rate, {{{1/2x}}}

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{{{1/x+1/(2x)=1/6}}}
Simplify and solve.


{{{6x(1/x+1/(2x))=6x(1/6)}}}

{{{6+3=x}}}

{{{highlight(x=9)}}}-------------hours for Andrea to do the job alone