Ratios & Proportions 7-1

Geometry

FRIDAY, Nov. 4

PRE-ASSESSMENT – 7 MIN

DO NOT WRITE ON THE CLASS SET USE YOUR OWN SHEET OF PAPER

Warm-Up

Vocabulary

Ratio: a comparison of two quantities. A ratio of a : b or a to b can be written as when b ≠ 0.

Proportion: a statement that two ratios are equal. Proportions can be written in these forms:

Extended Proportion: When three or more ratios are equal.

ab

cd

ab

and a : b = c : d=

14

416

624

==

Properties of Proportions

Vocabulary

Cross-product property: the product of the extremes is equal to the product of the means.

Scale Drawing: a drawing in which all lengths are proportional to corresponding actual lengths.

Scale: the ratio of any length in a scale drawing to the corresponding actual lengths.

Real Life Applications

Name a time when you would use ratios or proportions in your day to day life.

How would you use them?

Sample Problems

Sample Problems

Sample Problems

Homework

Practice Worksheet 7-1