Question 1195566
<pre>
COFFEE       PRICE           QTY        COST
   A          4.60            a
   B          5.70           2a
blend                                   640.00
</pre>

<pre>
COFFEE       PRICE           QTY        COST
   A          4.60            a          4.6a
   B          5.70           2a         5.7*2a
blend                                   640.00
</pre>
{{{highlight_green(4.6a+5.7*2*a=640)}}}

{{{(4.6+11.4)a=640}}}

{{{a=640/(4.6+11.4)}}}

{{{a=640/cross(15)}}}
{{{a=640/16}}}

{{{cross(a=42&2/3)}}}
{{{highlight(a=40)}}}