White vinegar is a solution of acetic acid in water. There are two strengths of white vinegar, 5% solution and a 10% solution. How many milliliters of each solution must be mixed to make 50 mL of a 9% solution?

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Answer:

10mL of the 5% solution and 40mL of the 10% solution

Step-by-step explanation:

To get the amount of each solution in milliliters that must be mixed to male 50ml of a 9% solution,

First let us represent the amount of 5% solution as A

Furthermore, let us represent the amount of 10% solution as B

From the question we know that A + B = 50ml

Hence 5% = 0.05 and 10% = 0.10

Then we get

0.05A + 0.10B = 0.09(A+B)

Then we solve further to get

Also, from A+B=50

A = 50 - B

0.05(50 - B) + 0.1B = 0.09(50 - B + B)

2.5 - 0.05B + 0.1B = 4.5

0.05B = 2

B = 40mL

And we know that A+B = 50,

Hence

40+A = 50

A= 50-40 = 10mL

By solving a system of equations, we will see that we must use 40 ml of the 10% solution and 10 ml of the 5% solution.

Writing a system of equations:

First, we need to define the variables that we will be using.

  • x = milliliters of the 5% solution used.
  • y = milliliters of the 10% solution used.

We know that we want to make 50ml of solution, then:

x + y = 50

And that solution must have a concentration of 9%, so the concentration in the left side must be the same one as on the right side, so we get the equation:

0.05*x + 0.10*y = 0.09*50

Then we got a system of equations:

x + y = 50

0.05*x + 0.10*y = 0.09*50

To solve this, first we need to isolate one of the variables in one of the equations, I will isolate x on the first one to get:

x = 50 - y.

Replacing that on the other equation we get:

0.05*(50 - y) + 0.10*y = 0.09*50

2.5 - 0.05*y + 0.10*y = 4.5

2.5 + 0.05*y = 4.5

0.05*y = 4.5 - 2.5 = 2

y = 2/0.05 = 40

Then we must use 40 milliliters of the 10% solutions, and the other 10 milliliters will be of the 5% solution

If you want to learn more about systems of equations, you can read:

https://brainly.com/question/13729904