need help with an algebra problem

Question

3. Melanie needs to mix a 32% saline solution with a 58% saline solution to create 200 milliliters of a 42.33% solution. How many milliliters of each solution must she use? You must show the equation used to solve this problem.

 

Answer 1

Hi Shauna

Since you did not mention if you wanted your numbers rounded, I rounded to the nearest half a ml

79.5 mls of 58% solution

120.5 mls of 32 % solution

Let x = volume of the 58 % solution

Let y = volume of the 32% solution

You can use a substitution since you need a total amount of 200 at 42.33%

Start with an Equation for the total volume below

x + y = 200

Put y in terms of x

y = 200 -x

Include the given concentrations below with everything in terms of x

.58x + .32(200 -x) = 200(.4233)

.58x + 64 - .3x = 84.66

Can you continue from here? If you have any questions just send a message

I hope this helps.