Page 187 - Maths Class 04

2. a. 1, 2, 3, 4, 6, 9, 12, 18, 27, 36, 54, 108 b. 1, 2, 4, 7, 8, 14, 28, 56
c. 1, 2, 3, 4, 6, 8, 9, 12, 16, 18, 24, 36, 48, 72, 144 d. 1, 89 e. 1, 2, 5, 10, 25, 50
3. a. 96; 1, 2, 3, 4, 6, 8, 12, 16, 24, 32, 48, 96, b. 180; 1, 2, 3, 4, 5, 6, 9, 10, 12, 15, 18, 20, 30, 36, 45, 60, 90, 180
c. 168; 1, 2, 3, 4, 6, 7, 8, 12, 14, 21, 24, 28, 42, 56, 84, 168 d. 55; 1, 5, 11, 55
4. 2, 3, 17, 19, 23, 29, 41, 37, 53, 43, 97, 101, 13, 7
Practice 5.2
1. a. 15 b. 2 c. 4 d. 12 e. 4 f. 24
g. 15 h. 225 i. 3 j. 3 k. 5 l. 5
2. a. b. c. d. e.
50 63 81 100 136

2 25 3 21 3 27 2 50 2 68

5 5 3 7 3 9 2 25 2 34

3. a. 1, 7 b. 1, 2, 3, 6 c. 1, 3
d. 1, 2, 4 e. 1, 3 f. 1, 2, 4 3 3 5 5 2 17
g. 1, 2, 13, 26 h. 1, 2, 3, 6
Practice 5.3
1. a. Prime b. Composite c. Composite d. Composite e. Prime f. Composite
2. 3, 11, 2, 23, 5, 41, 47, 29, 53 3. 15, 51, 92, 21, 80, 8, 62, 49, 32, 4, 18
Practice 5.4
1. a. 7 b. 3 c. 3 d. 7 e. 7 f. 3 g. 7 h. 3
2. a. 500; Even 3. 221; Odd
Practice 5.5
1. a. 200, 250, 300 b. 36, 45, 54 c. 56, 70, 84 d. 64, 80, 96 e. 68, 85, 102 f. 96, 120, 144
2. a. 8, 16, 24, 32, 40 b. 6, 12, 18, 24, 30 c. 12, 24, 36, 48, 60 d. 14, 28, 42, 56, 70
e. 15, 30, 45, 60, 75
3. a. True b. True c. False d. True e. False f. True g. False
Practice 5.6
1. a. 10, 20 b. 12, 24 c. 15, 30
2. Multiples of 5 = 5, 70, 80, 35, 95, 100, 50, 40, 15, 20, 10, 30, 25, 45
Multiples of 7 = 7, 28, 70, 35, 14, 98, 63, 21, 28, 42, 84, 56, 77, 49
3. a. 143,195 b. 154, 210 c. 121, 165 d. 77, 105 e. 11, 15 f. 176, 240
4. a. 12, 24, 36, 48 b. 36, 72, 108, 144 c. 21, 42, 63, 84 d. 24, 48, 72, 96
e. 10, 20, 30, 40 f. 33, 66, 99, 132
5. a. 3 b. 9 c. 5 d. 5 e. 5 f. 8 g. 3 h. 4
Practice 5.7
1. a. 18, 36, 54, 72, 90, 108, 126, 144, 162, 180
20, 40, 60, 80, 100, 120, 140, 160, 180, 200 \ LCM = 180
b. 9, 18, 27, 36, 45, 54, 63, 72, 81, 90
15, 30, 45, 60, 75, 90, 105, 120, 135, 150 \ LCM = 45
c. 4, 8, 12, 16, 20, 24, 28, 32, 36, 40
6, 12, 18, 24, 30, 36, 42, 48, 54, 60 \ LCM = 24
8, 16, 24, 32, 40, 48, 56, 64, 72, 80
d. 9, 18, 27, 36, 45, 54, 63, 72, 81, 90
15, 30, 45, 60, 75, 90, 105, 120, 135, 150 \ LCM = 90
18, 36, 54, 72, 90, 108, 126, 144, 162, 180
e. 16, 32, 48, 64, 80, 96, 112, 128, 144, 160
20, 40, 60, 80, 100, 120, 140, 160, 180, 200 \ LCM = 80
10, 20, 30, 40, 50, 60, 70, 80, 90, 100
2. a. 54, 108, 162, 216, 270 b. 42, 84, 126, 168, 210 c. 75, 150, 225, 300, 375
d. 18, 36, 54, 72, 90 e. 60, 120, 180, 240, 300

Mathematics-4 187