23 Geometry Bell Ringer Solve the following proportion

2/3 Geometry Bell Ringer Solve the following proportion: Reduce the following fraction: Homework: Proportion Word Problems IP

2/3 News and Notes • Homework Checked? • Perfection Award (from Tues): 2 nd Period

Today’s Plan • Use ACT-type problems to set up and solve proportions.

One Example on reducing fractions Step 1: List factors to find GCF Factors: 1, 2, 3, 4, 6, 12 Factors: 1, 2, 4, 7, 14, 28 Greatest Common Factor = 4

Step 2: Divide both by GCF

Example #1 • Strategy 1: Draw a Picture! One side of a rectangle measures 9 inches. The corresponding side of a similar rectangle measures 3 inches. If the other side of the original rectangle measures 18 inches, how long is its corresponding side in the similar rectangle? 18 3 9 x 9 x = 18(4) 9 x = 54 9 x/9 = 54/9 X=6

Example 2 • Strategy 2: Underline Important Information! Lil’ Wayne makes $5, 000 in 1 day. How much money does he make in 30 days? Corresponding Parts: 1 day and 30 days Corresponding Parts: $5000 and $x 30(5, 000) = x $150, 000 = x

Guided Practice • You have 1 minute to write the correct proportion on your notecard. Use notebook paper to show work. The pre-image of an isosceles triangle has legs of 11 inches and a base of 2 inches. If the image triangle is similar and has a base of 8 inches, how long are the legs?

Guided Practice • Now you have 1 minute to solve that proportion on notebook paper. Then write your answer on the back of your notecard. 11(8) = 2 x 88/2 = 2 x/2 44 = x

GP #2 – Same Process, New Problem • A recipe for 10 servings of pancakes calls for 3 cups of flour. How many cups of flour are needed if you want enough to feed a class of 45 students?

3(45) = 10 x 135/10 = 10 x/10 13. 5 cups = x

Independent Practice • Three tiers of problems: • Tier 1: Solving proportions, basic word problems. • Tier 2: Tougher word problems. • Tier 3: Challenging ACT proportions problems.