Question 902532
a+b=20,
0.75*a+0.25*b=0.4*20
a=20-b
0.75*(20-b)+0.25*b=8
15-0.75b+0.25*b=8
-0.5*b=-7
b=14
a=20-b
a=6 liter at 75% b=14 liter at 25%
check
0.75*6+0.25*14=0.4*20
4.5+3.5=8
8=8
ok