This is the second part of a series of post on Solving Ratio Problems. In the **first part**, we have learned how to solve intuitively and algebraically problems involvingĀ ratio of two quantities. In this post, we are going to learn how to solve a ratio problem involving 3 quantities.

**Problem 2**

The ratio of the red, green, and blue balls in a box is 2:3:1. If there are 36 balls in the box, how many green balls are there?

*Solution and Explanation*

From the previous, post we have already learned the algebraic solutions of problems like the one shown above. So, we can have the following:

Let be the number of grous of balls per color.

So, there are 6 groups. Now, since we are looking for the number of green balls, we multiply x by 3.

So, there are 6 groups (3 green balls per group) = 18 green balls.

**Check:**

From above, is the number of blue balls. The expression 2x represent the number of red balls, so we have 2x = 2(6) = 12 balls. Therefore, we have 12 red balls, 18 green balls, and 6 blue balls.

We can check by adding them: 12 + 18 + 6 = 36.

This satisfies the condition above that there are 36 balls in all. Therefore, we are correct.