Free preview Module 1: Ratios and proportional relationships

Topic A: Proportional relationships

▶ Intro to proportional relationships

To know if a relationship is proportional, you should look at the ratios between the two variables. If the ratio is always the same, the relationship is proportional. If the ratio changes, the relationship is not proportional.

⏱ 3:50 💾 4.2 MB License: cc-by-nc-sa Streaming via CDN

▶ Proportional relationships: spaghetti

Given a table of ratios, watch as we test them for equivalence and determine whether the relationship is proportional.

⏱ 1:03 💾 1.1 MB License: cc-by-nc-sa Streaming via CDN

▶ Proportional relationships: movie tickets

When going to the movies, is the price you pay proportional to the number of tickets you buy?

⏱ 1:46 💾 5.9 MB License: cc-by-nc-sa Streaming via CDN

▶ Proportional relationships: bananas

A proportionality problem about eating bananas.

⏱ 2:57 💾 9.8 MB License: cc-by-nc-sa Streaming via CDN

▶ Proportional relationships: graphs

Learn how to tell proportional relationships by drawing graphs. Key idea: the graph of a proportional relationship is a straight line through the origin.

⏱ 7:19 💾 10.2 MB License: cc-by-nc-sa Streaming via CDN

▶ Proportional relationships

Sal determines which ratios are proportionate to a ratio provided in a context.

⏱ 4:03 💾 6.7 MB License: cc-by-nc-sa Streaming via CDN

▶ Is side length & perimeter proportional?

Sal answers the question by drawing a square and thinking about the relationship between side length and perimeter.

⏱ 2:39 💾 2.8 MB License: cc-by-nc-sa Streaming via CDN

▶ Is side length & area proportional?

Sal answers the question by drawing a square and thinking about the relationship between side length and area.

⏱ 3:46 💾 3.6 MB License: cc-by-nc-sa Streaming via CDN

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