Answer:
25 mL of the 10% solution.
Explanation:
<em>Clayton will mix x milliliters of a 10%, percent by mass saline solution with y milliliters of a 20%, percent by mass saline solution in order to create an 18%, percent by mass saline solution.</em> This can be described with the following equation:
0.1 x + 0.2 y = 0.18 (x + y) [1]
<em>If Clayton uses 100 milliliters of the 20%, percent by mass saline solution, how many milliliters of the 10%, percent by mass saline solution must he use?</em>
If y = 100 mL, what should be the value of x?
Let's solve [1] for "x" and replace with the value of "y".
0.1 x + 0.2 y = 0.18 (x + y)
0.1 x + 0.2 y = 0.18 x + 0.18 y
0.02 y = 0.08 x
x = 0.25 y = 0.25 × 100 mL = 25 mL
