Question 1169907
<pre>
                          %B1     qty B1         %B2      qty B2

first powder    x          20      0.2x          30        0.3x

second powder   y          15     0.15y          10        0.1y

total(mg's)                       130                     180
</pre>
{{{system(0.2x+0.15y=130,0.3x+0.1y=180)}}}-----simplify and solve this system.