1. Lesson 7.1 , For use with pages 343-346 Write the fraction in simplest form. 1. 14 21 2. 25 55

2. Lesson 7.1 , For use with pages 343-346 Write the fraction in simplest form. 1. 14 21 2. 25 55 ANSWER 2 3 ANSWER 5 11

3. 7.1 Ratios and Rates

12. EXAMPLE 2 Using the Cross Products Property Write original proportion. Cross products property Multiply. Divide each side by 6.8 . Simplify. Check: You can check your solution by finding the cross products of the proportion. If the cross products are equal, the solution is correct. 6.8 15.4 = 40.8 m 6.8 m 6.8 = 628.32 6.8 m = 92.4 6.8 m = 15.4 (40.8) 6.8 m = 628.32

13. EXAMPLE 2 Substitute 92.4 for m . Multiply. Using the Cross Products Property 6.8 (92.4) 15.4 (40.8) = ? 628.32 628.32 = ? 6.8 15.4 = 40.8 92.4

14. GUIDED PRACTICE for Example 2 Solve the proportion. Then check your solution. Write original proportion. Cross products property Multiply. Divide each side by 54. Simplify. 5. 6 c = 54 99 6 (99) = 54c 594 = 54c 594 54 54c 54 = = 11 c 6 c = 54 99

15. Check: Substitute 11 for m. Multiply. GUIDED PRACTICE for Example 2 6 (99) 11 (54) = ? 594 594 = ? 6 11 = 54 99

16. GUIDED PRACTICE for Example 2 Solve the proportion. Then check your solution. Cross products property Multiply. Divide each side by 84. Simplify. Write original proportion. 6. n 14 = 63 84 84 n = 14(63) 84 n = 882 84 n 84 882 84 = = n 10.5 n 14 = 63 84

17. GUIDED PRACTICE for Example 2 Check: Substitute 10.5 for m. Multiply. 10.5 (84) 14 (63) = ? ? 10.5 14 = 63 84 882 882 =

18. GUIDED PRACTICE for Example 2 Solve the proportion. Then check your solution. Cross products property Multiply. Divide each side by 2.1. Simplify. Write original proportion. 7. 2.1 0.9 = 27.3 y 2.1 y = 0.9(27.3) 2.1 y = 24.57 2.1 y 2.1 24.57 2.1 = = y 11.7 2.1 0.9 = 27.3 y

19. Check: Substitute 11.7 for m. Multiply. GUIDED PRACTICE for Example 2 (2.1) (11.7) 0.9 (27.3) = ? 24.57 24.57 = ? 2.1 0.9 = 27.3 11.7