1. 7-1 R ATIO AND P ROPORTION Answers to Warm Ups 1. 2. 3. 3:20 4. 2:15 5. 2 to 1

2. R ATIO : A COMPARISON OF 2 NUMBERS a:b a to b Must be in same units 12 in = 1 ft 5280 ft = 1 mi 100 cm = 1 m 10 mm = 1 cm 1000 mm = 1 m

3. E XAMPLE : S IMPLIFY THE RATIO 2 FT : 30 IN Method 1 * Feet 2 ft: 2.5 ft 20 : 25 4 : 5 Method 2 * Inches 24 in: 30 in 4 : 5

4. T RY O N O WN 1) 1 m: 52 cm 2) 10 mm: 3.2 cm 3) 1.25 ft: 3 in Answers: 1) 25:13 2) 5:16 3) 5:1

5. E XAMPLE : LET X = 2 AND Y = 3 6x 2 to 12xy 6(2) 2 to 12(2)3 6(4) to 12(6) 24 to 72 4 to 12 1 to 3

6. T RY O N O WN : X = 2 AND Y = 3 1) 2) 3) Answers: 1) 2) 3)

7. E XAMPLE : S IMPLIFY *Divide Whole Numbers *Subtract Exponents

8. T RY O N O WN : S IMPLIFY 1) 2) 3) Answers: 1) In Simplest Form 2) 3)

9. E XAMPLE The ratio of the angles of a triangle are 4:4:7. Find the measure of each angle. *Usually we reduce by dividing. Now we will work backwards by multiplying 4x + 4x + 7x = 180 15x = 180 x = 12 4x = 4(12) = 48 7x = 7(12) = 84

10. T RY ON O WN 1) The ratio of the measures of 2 complementary angles is 1:2. Find the measure of each angle. 2) The measures of the angles of a pentagon are in the ratio 1:2:3:6:15. Find the measure of each angle. Answers: 1) 30,60 2) 20,40,60,120,300

11. H OMEWORK Pg 243 #1-31