The document discusses ratios and proportions. It defines ratios as a way to compare quantities in two or more groups, and notes that ratios are similar to but not the same as fractions. It provides examples of equivalent ratios and using cross-multiplication to determine if ratios are equivalent proportions. The document also discusses using variables like n to represent unknown values in ratios or word problems involving ratios.

1. Module 6 Ratios and Proportions

2. Ratios are used to compare the number of objects in two or more groups.

3. 1. No. of adults ___ 2. No. of children ___ The ratio of children to adults is 3 : 2. The ratio of adults to children is 2 : 3.

4. Ratios are not the same as fractions but they are similar. We can have equivalent ratios just like we have equivalent fractions The order in ratios is important .

5. Equivalent Fractions Question: Are the fractions below equivalent? 1 x 6 = 6 2 x 3 = 6 Answer pages 7- 8 Therefore, the fractions are equivalent . Cross multiply, Answer page 4

6. Equivalent Ratios Write two more equivalent ratios for the ratio given. Teachers to 1 : 4 = _______ = _________ Students

7. Equivalent Ratios Write two more equivalent ratios for the ratio given. girls to 3 : 1 = _______ = _________ boys Answer page 10

8. Fraction and Ratio

9. Are the ratios equivalent (proportion)? 1 : 5 and 3 : 15

10. Are the ratios equivalent (proportion)? 2 : 3 and 6 : 9 Complete Ex 1.1 pp 14 – 16 Now do page 12 Finish the back of the hand out

11. Sometimes one of the numbers in a proportion is not known. We want to find the number that will make the ratios equivalent. Cross-multiply to find the value of " n ". We want these ratios to be equivalent. We do not know the value of " n ". Look at the ratios. n : 4 and 2 : 8 Use a letter to represent the unknown number. Write n = 2 4 = 8

12. Finding the value of “n” (to make the ratios equivalent) n : 12 and 20 : 48

13. Finding the value of “n” (to make the ratios equivalent) 6 : 9 and n : 12 Do the questions on page 19

14. Word Problems Laila walks 4 km in 2 hour. How far ( n km ) can she walk in 7 hours ?

15. Word Problems Fatmah buys 5 kilograms of tomatoes for Dh 21. How much does 15 kilograms of tomatoes cost ( n Dh )?

16. 5 grams of gold costs Dh 430 . Word Problems How many ( n ) grams of gold can I buy for Dh 645 ?

17. Word Problems Answer page 21 – 24, Complete Ex 1.2 pp 26, 27 Hind can type 65 words per minute . How many ( n ) words does she type in 25 seconds ?