We’ll walk through several examples below: turning fractions to percentages; backing sales tax out of totals; percentage of total; percentage increase or decrease; percentage of completion ...

Fractions are a way of expressing parts ... quantities can be calculated and are in direct proportion when they increase or decrease.

Using a number line to show fractions can be a very helpful way ... but the numerators are the numbers that increase or decrease, while the denominators stay exactly the same.