Unit 9 Lesson 3: Exercise 3

1) A good science book has pictures and text in the ratio 4:8. In a science book I have just looked at, the picture occupy 23 pages. Approximately how many pages of text should this book have to be a “good” science book?

2) Zaid is making a drink from orange, pineapple and ginger juice in the ratio 40:9:1. If Zaid has only 4litres of orange juice, how much of the other two ingredients does Zaid need to make the drink?

3) A blend of drink is made by mixing pineapple juice with apple juice in the ratio 3:5 .I have a lot of apple juice but only 600litres of pineapple juice. What is the maximum litre of blend of drink that I can make?

4) A teacher always arranges the content of each of his lessons as teaching and practicing learnt skill in the ratio 2:3.

1) If a lesson lasted 45 minutes, how much teaching would he do?

2) If he decided to teach for 30 minutes, how long would the lesson last?

5) There is a group of student waiting for a school bus. 30 girls get on the first bus. The ratio of boys to girls at the stop is now 3:2. 15 boys get on the second bus. There is now equal number of boys to girls at the bus stop. How many students altogether were originally at the bus stop?

6) Chemicals x, y and z are added in the ratio of 1:4:2. If 60 ml of y is used, what is the measure of the other two chemicals?

7) The three sides of a triangle are in the ratio 2:3:1. If the triangle has it longest side to be 21.75cm, calculate the perimeter of the triangle.

8) The total enrollment in a school is 432.The ratio of the number of boys to girls’ is 5:4. How many more boys than girls are in the school?

9) At the start of the month a shop had 20-inches and 40-inches television sets in the ratio 4:5. By the end of the month, 200 20-inches and 500 40-inches were sold and the ratio of 20-inches to 40-inches television sets became 1:1. How many television sets of each type were there at the start of the month?

10) At the start of the week a bookshop had science and art books in the ratio 2:5. By the end of the week, 20% of each type of books were sold and 2240 books of both types were unsold. How many books of each type were there at the start of the week?