<PRE><B>Question 268138</B>
A druggist mixes a 10% solution of iodine with a 15% solution of iodine.
 How much of each solution should be used in order to obtain 20 cubic centimeters of a 12% solution? 
:
Let x = amt of 15% solution
then
(20-x) = amt of 10% solution
:
A typical mixture equation
.15x + .10(20-x) = .12(20)
.15x + 2 - .10x = 2.4
.15x - .10x = 2.4 - 2
.05x = .4
x = {{{.4/.05}}}
x = 8 cc of 15% solution required
then
20 - 8 = 12 cc of 10% solution
;
:
Check answer in original mixture equation
.15(8) + .10(12) = .12(20)
1.2 + 1.2 = 2.4</PRE>