6.3.5 Ratio and Rate Problems
Ratio and Rate Problems
Two methods are given, both equally good, though I will primarily be focused on the equivalent fractions method. You will notice that with the equivalent fractions, the totals are in the denominator while what you're looking for (in this case, how many like gel toothpaste) are in the numerator.
Since 3 x 50 equals 150, we will also multiply the numerator (2) by 50 as well in order to get our final answer of 100.
We can also use a process called Cross-Multiply and Divide. Using this method, we would take 2 x 150 (since they are across from each other) and then divide by 3. You will get the same answer.
This is just another example of using equivalent fractions in order to solve a multi-step problem. We could easily solve this using our cross-multiply and divide method as well and do it in one step. I've listed out the way to do that below. With this setup, we can cross multiply and divide right away to solve.
Homework:
