SETTING UP AND SOLVING PROPORTIONS SET UP THE

SET UP THE PROPORTION AND SOLVE! � If 12 bananas weigh 3 lbs, how

FIRST SET IT UP THEN USE CROSS PRODUCTS TO SOLVE � � Multiply 15

CROSS PRODUCTS SHORT CUT � 12 � Since x 15= 180 � 180÷ 3

SOLVING WITH ALGEBRA ANOTHER WAY � 12 � � x 15 = 3 x

MULTIPLE WAYS TO SET UP PROPORTION IF 12 BANANAS WEIGH 3 LBS, HOW MUCH

MULTIPLE WAYS TO SET UP PROPORTION YOU MULTIPLY THE SAME NUMBERS ANY WAY YOU

SOLVING WITH ALGEBRA � � � � 156 x 3 = 12 x 468

NEW TYPE OF PROBLEM. � If I can get 2 lbs of chocolate stars

� It is pretty easy to solve using cross products, but there is also

DIFFERENT TYPE OF PROBLEM. � If I can get 4 lbs of chocolate stars

� If a group can wash 10 cars in 12 minutes at a fundraiser,

CAN YOU FIGURE IT OUT AN EASIER WAY? � If a group can wash

USING SIMPLIFYING SHORTCUT 6 x 3 = 18 so � 5 x 3 =

A LITTLE TOUGHER NOW! � If I can grade 25 warmups in 2 hours,

THE ANSWER IS? ? ? � 62. 5 which rounds to 63!

YOU CAN DO IT!!!!! � My Roundup weed killer says to mix 4 fl

AND THE ANSWER IS ? ? ? 4 x 40 = 128 x �

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SETTING UP AND SOLVING PROPORTIONS!

SET UP THE PROPORTION AND SOLVE! � If 12 bananas weigh 3 lbs, how many bananas would weigh 15 lbs?

FIRST SET IT UP THEN USE CROSS PRODUCTS TO SOLVE � � Multiply 15 times 12 and then divide by 3. If there is a shortcut go ahead and use it!

CROSS PRODUCTS SHORT CUT � 12 � Since x 15= 180 � 180÷ 3 = 60 � 60 bananas 3 goes into 15 five times, just multiply both the top and bottom number by 5. � 12 x 5 = 60 � 60 bananas

SOLVING WITH ALGEBRA ANOTHER WAY � 12 � � x 15 = 3 x 180 = 3 x 3 3 60 = x x 15 = 3 x � 180 ÷ 3 = 3 x ÷ 3 � 60 = x

SET UP THE PROPORTION AND SOLVE! � If 12 bananas weigh 3 lbs, how much would 156 bananas weigh?

MULTIPLE WAYS TO SET UP PROPORTION IF 12 BANANAS WEIGH 3 LBS, HOW MUCH WOULD 156 BANANAS WEIGH?

MULTIPLE WAYS TO SET UP PROPORTION YOU MULTIPLY THE SAME NUMBERS ANY WAY YOU SET IT UP!

SOLVING WITH ALGEBRA � � � � 156 x 3 = 12 x 468 = 12 x 12 12 39 = x 156 bananas would weigh 39 lbs. � � 156 x 3 = 12 x 468 ÷ 12= 12 x ÷ 12 39 = x

NEW TYPE OF PROBLEM. � If I can get 2 lbs of chocolate stars for $6, how much would it cost for 3 lbs?

� It is pretty easy to solve using cross products, but there is also a relationship between the numerator and denominator. Use this shortcut when you can! � � 2 x 3 equals 6, so 3 x 3= 9 The answer is $9

DIFFERENT TYPE OF PROBLEM. � If I can get 4 lbs of chocolate stars for $6, how much would it cost for 3 lbs? � The answers are not always going to be whole numbers! � 18 ÷ 4 = $4. 50

� If a group can wash 10 cars in 12 minutes at a fundraiser, how many cars can be washed in 18 minutes?

CAN YOU FIGURE IT OUT AN EASIER WAY? � If a group can wash 10 cars in 12 minutes at a fundraiser, how many cars can be washed in 18 minutes? � If you simplify the ratio, then there is an easy shortcut!

USING SIMPLIFYING SHORTCUT 6 x 3 = 18 so � 5 x 3 = 15 � 15 cars can be washed in 18 minutes �

A LITTLE TOUGHER NOW! � If I can grade 25 warmups in 2 hours, how many warmups can I grade in 5 hours? � (Round to the nearest paper)

THE ANSWER IS? ? ? � 62. 5 which rounds to 63!

YOU CAN DO IT!!!!! � My Roundup weed killer says to mix 4 fl oz of concentrate for each 128 fl oz of water. If I have a spray bottle that holds 40 fluid oz of water, how much Roundup concentrate should I add?

AND THE ANSWER IS ? ? ? 4 x 40 = 128 x � 160 = 128 x � 160 ÷ 128 = 128 x ÷ 128 � 1. 25 = x � The answer is 1. 25 or 1¼ fl. oz. concentrate �

WHAT QUESTIONS DO YOU STILL HAVE?