Math Example: Percents with Double Number Lines: Example 10

Topic

Ratios, Proportions, Percents

Description

This example demonstrates how to determine an unknown value using a double number line when given a part and its corresponding percentage, involving a decimal percentage. The image shows two number lines: one ranging from 0 to 100% and another from 0 to an unknown number x. The position 70 is marked on the second line, visually illustrating the process of finding x when 70 is 12.5% of x.

Double number lines are powerful tools for teaching percentages as they provide a clear visual representation of the relationship between percentages and their corresponding numerical values. This collection of examples covers various scenarios, including finding the whole when given a part and a decimal percentage.

Presenting multiple worked-out examples is crucial for students to fully grasp the concept of percentages using double number lines. Each example builds upon the previous one, gradually increasing in complexity and addressing different types of percentage problems. This approach allows students to recognize patterns, develop problem-solving strategies, and gain confidence in applying the double number line method to various percentage calculations, even those involving decimal percentages.

Teacher Script: "Let's look at this interesting example where we need to find the whole when given a part and a decimal percentage. We're told that 70 is 12.5% of some number. Using our double number line, we can visually represent this problem. Notice how 70 aligns with 12.5% on our percentage line. This helps us see that 70 is one-eighth of our unknown number. If 70 is one-eighth, what's the whole number? That's right, it's 560. This visual method helps us understand the relationship between percentages, including decimal percentages, and the numbers they represent. It's particularly useful when dealing with percentages that might be harder to work with mentally."

For a complete collection of math examples related to Percentages click on this link: Math Examples: Percents and Double Number Lines Collection.