Question 1154140
<pre>
BROTHER           1/b

SISTER           1/(b+5)

Combined         1/6
</pre>


{{{1/b+1/(b+5)=1/6}}}

-

{{{(b+5)+b=(b^2+5b)/6}}}

{{{2b+5=(b^2+5b)/6}}}

{{{12b+30=b^2+5b}}}

{{{b^2-7b=30}}}

Maybe  {{{3*10=30}}} comparing {{{b(b-7)=30}}},  {{{b=10}}}.


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<pre>
PERSON        TIME to do ONE JOB

BROTHER           10

SISTER           15

Combined         6
</pre>