3.) Now we solve the equation we found in step 2 using algebra.
4.) We see that s = 30 gallons, so we should add 30 gallons of our 30% oil solution to our 15 gallons of our 15% oil solution to obtain a 25% oil solution.
Please please don't skip them I promise if you try you guys you can do them.
There's a certain kind of word problem we're going to look at today and that's where you're looking at the amount of cost and the amount of quantities that go into a mixture.
Suppose you have a jug of 120 ounces of juice that is 20% pure apple juice and the rest is water.
You feel this is a bit too sweet, so you want to add water to the juice so that your new juice is 15% pure apple juice. Solution: 1.) Your unknown quantity is how much water you should add to your juice. 2.) We want to set up an equation in w with the information given.
3.) Use algebra to solve the equation for the variable. We want to look at multiple examples to practice solving mixture problems.
In each of the following practice problems, we will use the four steps listed above as a guide to help us solve the problem.
Putting this all together to create an equation, we recognize that the amount of oil in the 15% solution (2.25 gallons) plus the amount of oil in the added 30% solution (0.30s gallons) will be equal to the amount of oil in the desired final mixture (0.25(s 15) gallons).
In equation form, we have 2.25 0.30s = 0.25( s 15).