<PRE><B>Question 231931</B>
How many liters of a 20% salt solution must be mixed with 30 liters of an 60%
 salt solution to obtain a 30% salt solution?
:
Let x = amt of 20% solution required
:
Write an amt of salt equation using the decimal equiv
.20x + .60(30) = .30(x+30)
.20x + 18 = .30x + 9
18 - 9 = .30x - .20x
9 = .10x
x = {{{9/.1}}}
x = 90 liters of 20% solution 
:
:
See if this is true
.2(90) + .6(30) = .3(90+30)
18 + 18 = .3(120); confirms our solutio</PRE>