Question

A pharmacist mixed some 10%-saline solution with some 15%-saline solution to obtain 100 mL of a 12%-saline solution. How much of the 10%-saline solution did the pharmacist use in the mixture?

A 60 mL
B 45 mL
C 40 mL
D 25 mL

Answer 1

its 60ml

Answer 2

how do I get it?

Answer 3

10/100*x +15/100(100-x)=12

check if you get this.
'x' is the volume of 10% solution.

Answer 4

Out of 100 ml you take x ml of 10% solution and the remaining 100-x ml of 15% solution.