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PROPORTIONS Section 1.6. We will use proportions to analyze proportional relationships and to solve real-life problems. WHAT THE HECK IS A PROPORTION ?. A relationship between two ratios that are _______________. WHAT DOES A PROPORTION LOOK LIKE? 4 = b 6 3.
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PROPORTIONSSection 1.6 We will use proportions to analyze proportional relationships and to solve real-life problems.
WHAT THE HECK IS A PROPORTION? A relationship between two ratios that are _______________. WHAT DOES A PROPORTION LOOK LIKE? 4 = b 6 3
WHAT IS A PROPORTION USED FOR? To find an ______ value in one ratio when given another ______ ratio. HOW DO WE SOLVE A PROPORTION? We find the ________, where we multiply the numerator of one ratio with the denominator of the other ratio.
LET’S PRACTICE DETERMINING IF TWO RATIOS ARE PROPORTIONAL *Step 1: Find the cross products *Step 2: Compare the cross products 30 30 2 = 10 3 15 YES!
LET’S PRACTICE DETERMINING IF TWO RATIOS ARE PROPORTIONAL *Step 1: Find the cross products *Step 2: Compare the cross products 15 = 9 12 6 NO!
WHITE BOARD TIME!! Is the following ratio proportional? 4 = 16 5 20
WHITE BOARD TIME!! Is the following ratio proportional? 6 = 18 10 30
WHITE BOARD TIME!! Is the following ratio proportional? 24 32 1 = 4 8 24
Try on your Own • 1. The ratio of 7th grade students to 8th grade students in a soccer league is 17:23. If there are 200 students in all, how many are in the 7th grade?
Try on your Own • 2. After 2 hours, the air temperature had risen 8 degrees. Write and solve a proportion to find the amount of time it will take at this rate for the temperature to rise and additional 13 degrees.
Use Unit Rate • You can also use the unit rate to write an equation expressing the relationship between two proportional quantities. • Example: Olivia bought 6 containers of yogurt for $7.68. Write an equation relating the cost c to the number of yogurts y. How much would Olivia pay for 10 yogurts at this same rate?
Practice • Solve each proportion: • 1. k = 32 7 56 • 2. 3.2 = n 9 36 • 3.Evarado paid $1.12 for a dozen eggs at his local grocery store. Determine the cost of 3 eggs.
Essential Question • How do you solve a proportion? • ________________________________________________________________________________________________________________________________________________________________________________________________