Page 379 - Start Up Mathematics_8 (Non CCE)

Exercise 3.5 4. No, for example,
2
2
1. (a) 2 (b) 3 (c) 3 (d) 3 1 + 2 = 1 + 4 = 5 which is not a square number
2
2
2. (a) 201 (b) 21 (c) 1,111 (d) 82 2 – 1 = 4 – 1 = 3 which is again not a square number
(e) 693 (f) 826 (g) 2,534 (h) 18,897 Let’s Evaluate
3. (a) 42 (b) 85 (c) 124 (d) 56 1. (a), (c) 2. (a) 69 (b) 123 (c) 305
4. (a) 89 (b) 93 (c) 9 (d) 85 3. (a) 4,624 (b) 1,156 (c) 8,464
5. 9,801 6. 961 7. 10,000 4. (a) 9,409 (b) 3,481 (c) 784
8. 1,00,04,569 9. 1,104 m 5. (a) 68 (b) 60 (c) 89
Exercise 3.6 6. (a) 56 (b) 139 (c) 26.38
7. (a) 6.537 (b) 0.099 (c) 1.518
85 47 124 999
1. (a) (b) (c) (d) Thinking Skills
33 18 201 74
21 1 16 136 1. 576 2. 650 m 3. 13 m 4. 30 m 5. 84 m
(e) 1 (f) 5 (g) (h) 2 7 8
25 8 29 235
6. (a) 0 1 1 77,284
86 4 2 4 4 6
(i) (j) 1
78 13 1 4 5
7 4 9 6
2. (a) 800 (b) 1,890 (c) 225 (d) 10,290 1 5 6
8 8 6 6 4
3. 12 m 4. 36 cm 5. 30 m
9 3 1 5
Exercise 3.7 (b) 0 0 1 99,225
1. (a) 7.9 (b) 1.35 (c) 0.21 (d) 13.6 3 9 3 5
(e) 0.0271 (f) 0.052 (g) 1.49 (h) 8.63 1 0 0 0
(i) 15.34 (j) 7.35 3 1 5
2. 5.49 m 3. 872; 7.848 4. (56, 87); 4.613 5 1 5 0 5 2 5
5. (25, 21); 0.525
Exercise 3.8 Values and Life Skills
1. (a) 3.317 (b) 8.718 (c) 10.536 (d) 20.906 350
(e) 6.165 (f) 2.793 (g) 18.735 (h) 0.061 Exemplar Problems
(i) 6.420 (j) 1.025 (k) 0.004 (l) 1.414
2. 13.52784 3. (a) 8.49706 (b) 14.45914 (c) 30.61862 1. a 2. c 3. False 4. 5.3
(d) 70.71068 (e) 140.87228 4. 20.623 m 5. 8; 15 6. 3.3 m 7. 8,836
Review Exercises Chapter 4
Multiple Choice Questions Exercise 4.1
1. d 2. a 3. c 4. b 1. (a) 5,832 (b) 46,656 (c) 85,184 (d) 4,21,875
5. b 6. b
(e) 9,70,299 (f) 11,24,864 (g) 1,23,26,391
Solve Mentally 4. 3,025 5. (a), (b), (d), (c)
True or False 6. (a), (c), (e), (f) 7. (a), (c), (d), (f)
1. True 2. False 3. True 4. False 5. True 10. (a) 2 (b) 7 (c) 9 (d) 6
Fill in the Blanks (e) 5 (f) 4
1. not 2. 0, 1 3. odd 4. Pythagorean triplet 11. 2,197 cm 3
2
5. 13,225 6. 99,999 7. 7 = 49 8. 199 12. (a) 3 (b) 2 (c) 5 (d) 7
Answer in One Word or a Line (e) 3 (f) 4
1. Perfect squares are numbers whose exponent is 2, i.e., 14. (a) 8 times (b) 343 times
the number is raised to the power 2. 15. (a) 2,50,047 (b) 24,389 (c) 5,92,704 (d) 9,41,192
2. If three natural numbers a, b, c satisfy the condition (e) 97,336 (f) 32,768
2
2
2
a + b = c , then the numbers are said to form a 16. (a) 2,197 (b) 21,952 (c) 17,576 (d) 1,728
Pythagorean triplet. Yes 17. (a) 7 (b) 8 (c) 5 (d) 4
3. Negative numbers (e) 9 (f) 2
371