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? Also, what is the rate formula?

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?  Also, what is the rate formula?

mertsj · Answer

x= amount of 10% solution
100-x = amount of 15% solution
.10x+.15(100-x)=.12(100)

mertsj · Answer

Solve that.  x is the amount of the 10% solution the pharmacist needs.
I do not know what you mean by the rate formula.

anonymous · Answer

well, there is this formula, and it's used to solve rate problems, if it doesn't exist, that's fine, thanks by the way

mertsj · Answer

yw