Question 1146676
Add p kg of peat moss
Add v kg of vermiculite
Wanted:  15% peat moss and 15% vermiculite



{{{system((0.12*100+p)/(100+p+v)=0.15,(0.06*100+v)/(100+p+v)=0.15)}}}
Simplify and solve this system.


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{{{system(0.85p-0.15v=3,-0.15p+0.85v=9)}}}



{{{system(17p-3v=60,-3p+17v=180)}}}


If add corresponding members and simplify that, system to use can be
{{{system(7p+7v=120,17p-3v=60)}}}


If do E1 * 3, and E2 by 7, system is
{{{system(21p+21v=360,119p-21v=420)}}}


{{{p=39/7}}}

{{{highlight(p=5.6)}}}-------kilograms peat moss

-

{{{v=(120-7(39/7))/7}}}


{{{v=11&4/7}}}

{{{highlight(v=11.6)}}}----------kilograms vermiculite