Lesson: Ratio & Proportion Lesson 1
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.
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