Page 189 - Math Skill - 4

Answers 187

Assessment Time
A. 1. (c) 2. (b) 3. (a) 4. (b) 5. (a) 6. (a) B. 1. diameter 2. half 3. two 4. six C. 1. True 2. False
3. True 4. True 5. False 6. False 7. True 8. False D. 1. (i) 2. (iv) 3. (ii) 4. (i) 5. (iii)

Chapter 11: Perimeter and Area
Boot-up : 8o; (a) 14 cm (b) 12 cm (c) 15 cm (d) 13 cm
Exercise 11.1
1. (a) 18 cm (b) 20 cm (c) 20 cm (d) 26 cm (e) 52 cm (f) 40 cm 2. (a) 68 cm (b) 84 cm (c) 76 m 3. 52 m
4. 290 m 5. Rectangle has greater perimeter by 10 cm. 6. Carrot: 230 m Radish: 220 m, No they are not equal

Exercise 11.2
1. (a) 104 sq cm (b) 280 sq cm 2. (a) 6 sq cm (b) 12 sq cm (c) 10 sq cm
3. (a) 225 sq cm (b) 400 sq cm (c) 144 sq cm 4. 336 sq cm 5. 1296 sq cm

Assessment Time
A. 1. (a) 2. (c) 3. (a) 4. (b) 5. (a) B. 1. 75 m 2. 120 cm 3. 25 square cm 4. 12 square cm 5. 9 cm
C. 1. (ii) 2. (i) 3. (iii) 4. (i) 5. (iv)

Chapter 12: Patterns and Symmetry
Boot-up :

Exercise 12.1

1. (a) (b)

(c) (d)

2. (a) (b) 3. (a) (iv), (b) (iii), (c) (iii),

Exercise 12.2
1. (a) 21, 34, 55 Rule: Add the two previous numbers (b) 36, 41, 39 Rule: Add 5, subtract 2
(c) 101, 99, 94 Rule: Subtract 2, then 5 (d) 324, 972, 2916 Rule: Multiply by 3 to get the next term
2. (a) 1 + 2 + 3 + 4 + 5 = 15 1 + 2 + 3 + 4 + 5 + 6 = 21 1 + 2 + 3 + 4 + 5 + 6 + 7 = 28
(b) 444 ÷ 12 = 37 555 ÷ 15 = 37 666 ÷ 18 = 37 3. (a) 2 (b) 11 (c) 11

28 48 24
12 16 20 28 72 4 6
4. (a) (b) 8 12 16 (c) 6 12 (d)
5 7 9 2 2 3
2 3 4 5 3 5 7 9 2 3 4 1 2 1 3
1 2 3 4 5
Exercise 12.3
1. (a) I LOVE MATH (b) HOME SWEET HOME (c) MY MOTHER IS BEST
2. (a) 2 5 8 1 16 16 25 (b) 20 15 4 1 25 9 19 8 15 12 9 4 1 25
Exercise 12.4

1. (a) (b) (c) (d) (e) (f) (g) (h)

2. (a) No (b) Yes (c) Yes (d) Yes (e) Yes (f) No (g) Yes (h) No