Let x be the number of ounces of 30% vitamin C solution and let y be the number of ounces of 10% vitamin C solution that are needed to make 50 ounces of a 25% vitamin C solution.
x + y = 50 ...........(1)
y = 50 - x ............(2)
0.3x + 0.1y = 0.25 * 50 .......(3)
Plugging the expression for y in (2) into (3), we get:
0.3x + 0.1(50 - x) = 12.5 ......(4)
Expanding and simplifying (4) we get:
0.2x = 7.5
x = 37.5 .......(5)
Plugging the value of x in (5) into (2), we get:
y = 50 - 37.5 = 12.5
The answer is: 37.5 ounces of 30% vitamin C solution and 12.5 ounces of 10% vitamin C solution.
