Question 238771
In a chemistry class, 3 liters of a 4% silver iodide solution must be mixed with a 10% solution to get a 6% solution. 
How many liters of the 10% solution are needed?
;
Let x = amt of 10% solution required
:
Write a decimal equiv equation:
.04(3) + .10x = .06(x + 3)
:
.12 + .1x = .06x + .18
"
.1x - .06x = .18 - .12
:
.04x = .06
x = {{{.06/.04}}}
x = 1.5 liters of 10% solution required
;
;
Check in the original equation
.04(3) + .1(1.5) = .06(1.5+3)
.12 + .15 = .06(4.5)
.27 = .27; confirms our solution