Question 1138982
L=60
H=85
T=70
M=150
v, the volume of the H=85 material
M-v, volume of the L=60 material



{{{L(M-v)+Hv=TM}}}
-
{{{LM-Lv+Hv=TM}}}
{{{(H-L)v=TM-LM}}}

{{{highlight(v=(TM-LM)/(H-L))}}}


Substitute and then solve for v; use result to evaluate M-v.