Proportion noun comparative relation between things or magnitudes
Proportion: (noun) comparative relation between things or magnitudes as to size, quantity, number, etc. ; ratio. proper relation between things or parts. By: Jada Delpit and Gerica Dorsey
What are proportions? � Proportions are an equation where both sides are equal. � Cross products are how you solve proportions (cross multiplication) � Proportions can help you find what percent of your check is used for bills. � They can also help you find equivalent fractions.
How to set up a proportions? � There are two types of proportions: percent proportions and unit rates. � Percent proportions are set up: is/of = x/100. � Unit rates are set up: unit(x)/1=x/unit you’re given.
Equivalent Fractions � Equivalent Fractions are two fractions, set up in an equation that are equal to each other. � Equivalent fractions are set up: a/b=d/c
Examples of percent proportions…. . On your math test, you scored an 85%. You got 34 problems correct. How many problems were on the test? � Is/of =%/100 � 34/x=85/100 � Now, you cross multiply. � 34 x 100=3400 � Now, you divide. � 3400/85=40 � Therefore, the answer is 40 questions on the test. �
Examples of unit rates. …… On a map scale, 1 centimeter equal 22 inches. How many centimeters equal 10 inches? � Unit /1=x/unit you’re given � 22/1=x/10 � MULTIPLY! � 22 X 10=220 � DIVIDE! � 220/1= 220 � Therefore, 220 centimeters equal 10 inches. �
Look at me NOW Proportions Song!!!! Proportions Song, Gerica n Jada
YOU TRY!!!!!! � 436 is what percent of 250? � A. 230. 7% � B. 87. 9% � C. 174. 4% � D. 9. 16%
Here’s another! � 72 is 0. 04% of what number? � A. 32, 000 � B. 180, 000 � C. 97 � D. 87, 000
Constructed Response � Viktor earned $240 this month. He earned $150 of that money mowing lawns. What percent of the money he earned was earned by mowing lawns? � SHOW YOUR WORK!!!!!
Proportions also apply to real life situations › For example, if you wanted to know what you made on your math test in Mr. Pisciotta’s class, you can set up a percent proportion. › What you would do, is the number of questions you got right/ the number of questions on the test equals x/ 100.
Let’s try the percent proportion out! � If I made a 42 out of 50 on Mr. Pisciotta’s test, what percent of the questions did I get correct? � 42/46 = x/100 � MULTIPLY! 42 X 100= 4200 � DIVIDE! 4200/50= 84 � This means I got an 84% on Mr. Pisciotta’s test!
PICTURES!!!
You Try! A television station advertises 288 commercials every 24 hours. If the television station maintains this rate, how many commercials are being aired every 168 hours?
Thanks 4 Watching!!!!!! � This project is by Jada Delpit and Gerica Dorsey. If you have any last questions, please ask them!
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