1. Do Now 1/5/12 Take out HW from last night. Take out HW from last night. Text p. 156, #14-38 evens, 43, 48, 49 Text p. 156, #14-38 evens, 43, 48, 49 Copy HW in your planner. Copy HW in your planner. Text p. 160, #6-32 evens, 39, 40, 44, & 45 Text p. 160, #6-32 evens, 39, 40, 44, & 45 Quiz sections 4.1-4.3 Monday Quiz sections 4.1-4.3 Monday In your journal, decide which is the better buy? 350 minutes for $39.99 or 600 minutes for $52.99. How much money are you saving per minute? In your journal, decide which is the better buy? 350 minutes for $39.99 or 600 minutes for $52.99. How much money are you saving per minute?

2. Homework Text p. 156, #14-38 evens, 43, 48, 49 14) yes 14) yes 16) no 16) no 18) yes 18) yes 20) yes 20) yes 22) 27/60 = 9/20 22) 27/60 = 9/20 24) 121/99 = 11/9 24) 121/99 = 11/9 26) 5/22 = 15/66 26) 5/22 = 15/66 28) 27/72 = 3/8 28) 27/72 = 3/8 30) 8, 24, 32 32) 3:1, 9:3 34) 2:1, 4:2 36) 1/5, 2/10 38) 2 to 20, 3 to 30 43) a. 8 to 5 b. Mill Pond & Clear Pond 48) D 49) H

3. Objective SWBAT write and solve proportions SWBAT write and solve proportions SWBAT solve proportions using cross products SWBAT solve proportions using cross products

4. RATE – a fraction in which the numerator and the denominator have different units of measure. RATIO- uses division to compare two quantities of the SAME MEASURE.

5. Proportion- an equation that states that two ratios/rates are equivalent. Section 4.2 “Identifying and Writing Proportions” “a is to b as c is to d”

6. Solve a proportion by finding the value of the variable. One way to solve a proportion is to write both fractions with the same denominator (think of equivalent fractions). Section 4.3 “Solving Proportions”

7. Solve the Following Proportions: = = = = = = x = 9 x = 4 y = 30

8. Cross Products A CROSS PRODUCT is the product of the numerator of one ratio and the denominator of the other ratio in a proportion. If, then

9. Solve the Proportion If, then Divide both sides by 33

10. Write original proportion. 8 15 = x 6 Solve the proportion = 8 x615 Cross products property Simplify. 120 = 6x Divide each side by 6. 20 = x =8 x615 a 29 = 21 217 Cross products property 21 · 29 = 7 a 609 = 7a Simplify Divide both sides by 7. 87 = a 87 = a Solve the proportion a 29 = 21 217 Write original proportion.

11. The ship model kits sold at a hobby store have a scale of 1 ft : 600 ft. A completed model of the Queen Elizabeth II is 1.6 feet long. Estimate the actual length of the Queen Elizabeth II. The ship model kits sold at a hobby store have a scale of 1 ft : 600 ft. A completed model of the Queen Elizabeth II is 1.6 feet long. Estimate the actual length of the Queen Elizabeth II. Write and solve a proportion to find the length g of the Queen Elizabeth II. =1.6 g 1600 Cross products property g = 960 Simplify. 1 · g = 600 · 1.6 SOLUTION The actual length of the Queen Elizabeth II is about 960 feet.

12. Solving Equations with Rates A punch recipe calls for 4 cups of orange juice. The recipe will serve 8 people. You are making punch for a party of 32 people. How many cups of orange juice do you need? A punch recipe calls for 4 cups of orange juice. The recipe will serve 8 people. You are making punch for a party of 32 people. How many cups of orange juice do you need? =

13. Density is the ratio of a substance’s mass to its volume. The density of ice is 0.92 g/mL. What is the mass of 3 mL of ice?. Density is the ratio of a substance’s mass to its volume. The density of ice is 0.92 g/mL. What is the mass of 3 mL of ice?. Write and solve a proportion to find the mass of 3 mL of ice. = x 3 mL 3 mL 0.92 g 0.92 g 1 mL Cross products property x = 2.76 g Simplify. 1 · x = 3 · 0.92 SOLUTION The mass of 3 mL of ice is 2.76 grams.

14. Homework Text p. 160, #6-32 evens, 39, 40, 44, & 45 Text p. 160, #6-32 evens, 39, 40, 44, & 45 NJASK7 Prep