Question 1179767
L=7
H=12
T=8
M=350
v of the H conc.
M-v of the L conc.


{{{Hv+L(M-v)=MT}}}
-
{{{Hv+ML-Lv=MT}}}
{{{(H-L)v+ML=MT}}}
{{{(H-L)v=MT-ML}}}
{{{highlight_green(v=M((T-L)/(H-L)))}}}


Substitute the given values....