ensuring that student understand the meaning of important vocabulary, such as percentage as “in every hundred”, base as the unit of comparison, and amount as the target quantity.Use base amounts that make the calculations simpler, such as 60 or 30, before using more complicated bases such as 24, 36 and 144 Easier problems involve simple percentages such as 50%, and 10%, moving to derivatives of those percentages like 25%, 5%, and 30%. altering the numbers that you choose for the problem.The learning opportunities in this unit can be differentiated by providing or removing support to students, orby varying the task requirements. Contexts such as healthy eating guides, shopping discounts, statistics, and comparisons are encountered by students in their daily lives. This unit builds on students’ everyday knowledge of percentages. That calculation is equivalent to 30/100 x 45 = ? Common examples of percentages being used as operators are discounts in shops, and interest on loans. In other situations, percentages are used as a fractional operator, e.g. The number of boys is 150% of the number of girls. For example, there are 12 girls and 18 boys. In those situations, percentages greater than 100% are possible. Some situations involve comparison of different wholes or different parts. For example, Mani takes 30 shots, but Alicia takes 28 shots. Most situations in which part-whole relationships need to be compared, the whole (or bases) are not the same. Percentages are useful to establish a common base for comparison. There is an assumption of homogeneity, that Mani will shoot at the same rate. What is her shooting percentage? The percentage of Mani's shots landed is calculated as 24/30 = ?/100. For example, in the following problem Mani lands 24 out of 30 shots in her netball game. In many situations a percentage describes a part-whole relationship. So, a percentage literally means “for every hundred.”

The symbol %, is derived from the vinculum of a fraction: /, and the two zeros from 100.

Percentages are a specific type of equivalent fraction with a denominator of 100.

Figuring out percentages proportions