Lesson: Ratio & Proportion Lesson 1
Lesson Objective
Lesson Plan
Explore: Parts, Wholes, and Percents
Remember that a ratio is a comparison of 2 numbers
A proportion is an equation with 2 equivalent ratios.
A percent shows a number compared to 100. (aka a rate or ratio)
Look at the following problem using ACTIVE READING
Once there was a boy named Sam. He loved donuts. Everyday he would search all over the city for donuts. One day he found 150 donuts. He gave 20% of his donuts to his dog.
Comparing total donuts to those given to the dog.
Percent is a locked in ratio because its always out of 100.
Come up with labels then fill in what you know and solve together. May abbreviate units.
Units must be the same on each ratio.
Solving Percent Problems with Proportions
Percent problems always ask you to find part of something, the total, the percent.
Guided: Use active reading to help students identify what is missing in the word problem as they fill in the proportion.
Do next example together where percent is missing.
Independent Practice – Review first 3 on OHs.
Multiple Applications of Proportions
Throw in some examples that are comparing a part of something to the total – like some they’ve seen in PS class. Do the first example together…then set up the next two, they go and solve, going on to independent practice.
Lesson Resources
20100325  Use Prop w. Pcnts.PCKT.xls 
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