professor stevens wants to mix a solution containing 13% acid with one containing 18% acid to obtain a 50 milliliter solution containing 16% acid. How many milliliters of the 13% solution should the professor use?
Let x be the number of milliliters of the 13% solution used by Professor Stevens.
The equation for the acid content in the final mixture can be represented as:
0.13x + 0.18(50 - x) = 0.16(50)
Solving for x:
0.13x + 9 - 0.18x = 8
-0.05x = -1
x = 20
Therefore, Professor Stevens should use 20 milliliters of the 13% solution.