Question 1144999
Remove and replace v number of liters.

{{{(0.25*(12-v)+1*v)/12=0.45}}}

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{{{(3-0.25v+v)=12*0.45}}}

{{{0.75v+3=12*0.45}}}

{{{0.75v=12*0.45-3}}}

{{{v=2.4/0.75}}}

{{{highlight(v=3.2)}}}