Question 1011086
<pre>
                     RATES
certain old         {{{1/(x+2)}}}
new model           {{{1/x}}}
both combined       {{{1/x+1/(x+2)}}}</pre>

One job is "stamp a box of parts".


{{{(1/(x+2))5+(1/x+1/(x+2))3=1}}}----------Most important is that this make sense and you learn to formulate it yourself.


The rest is arithmetic.  Tell if you need more help.