<PRE><B>Question 146696</B>
You should take the average:
( 5% * x  +  20% * y ) / ( x + y ) = 8%
* x + y = 800
( 0.05x  +  0.2y ) / 800 = 0.08
* x = 800 - y
( 0.05( 800 - y )  +  0.2y ) / 800 = 0.08
( 40 - 0.05y  +  0.2y ) / 800 = 0.08
( 40  +  0.15y ) / 800 = 0.08
40  +  0.15y = 64
0.15y = 24
y = 160
Substitute: y = 160
x = 800 - y
x = 800 - 160 = 640
640ml of the 5% and 160ml of the 20%</PRE>