Ratio and Proportions

Trotter, Barbara Ole A. Thorp
545-0169

Objectives To read and write proportions To identify the means and extremes of a proportion To solve proportions To solve problems using proportions To make a scale drawing Material Needed: Overhead projector, transparencies, chalkboard, various samplings of appropriate materials, including worksheets, and scale drawings. Procedure: The teacher will open the session with a daily review of changing fractions to decimal and decimals to percents, from 1/1 to 1/5. The teacher will review the vocabulary (ratios, proportions, means, extremes, and scale drawings). Students will give definitions in their own words with an example. Teacher will then give several examples of ratios, soliciting verbal responses with examples from the class. This step is then repeated with proportions, extremes, and the mean. To determine if students have mastered the above concepts, they will complete a worksheet. The teacher will assign various students to do the even numbered problems at the board and those students seated will do the odd numbers. The class will orally discuss the problems and answers. The teacher will then give the class a model drawing of a house and boat. The house will be increased by a 1 to 3 ratio, and then decreased by a 3 to 2 ratio. The boat model will be increased by a 1 to 2.5 ratio. The teacher will then close the session with the verbal drill.