Page 201 - Math Skill - 5

Answers 199

Exercise 4.2
1. (a) (b) (c) (d) (e)

2. (a) 2 x 2 x 2 x 2 x 2 x 2 x 3 x 3 x 3 (b) 5 × 5 × 31 × 79 (c) 2 x 2 x 2 x 2 x 2 x 5 x 5 x 5 x 5 x 5
(d) 2 x 2 x 2 x 2 x 3 x 5 x 5 x 5 x 5 (e) 2 x 2 x 2 x 3 x 3 x 3 x 3 x 5 x 5 x 5
3. 14 = 2 x 7; 16 = 2 x 2 x 2 x 2; Common Factor = 2
4. 100 = 2 x 2 x 5 x 5; 250 = 2 x 5 x 5 x 5; 1600 = 2 x 2 x 2 x 2 x 2 x 2 x 5 x 5; Common Factors = 2 x 5 x 5

Exercise 4.3
1. (a) 25 (b) 16 (c) 100 (d) 105 (e) 5 (f) 12
2. (a) 1 (b) 1 (c) 1 (d) 11 (e) 72 (f) 225
Exercise 4.4

1. (a) 650 (b) 480 (c) 1080 (d) 756 (e) 375 (f) 3000
2. (a) LCM = 375 (b) LCM = 432 (c) LCM = 13310 (d) LCM = 9690 (e) LCM = 8250
HCF = 25 HCF = 36 HCF = 11 HCF = 10 HCF = 15
(f) LCM = 6261
HCF = 111
Exercise 4.5

1. After 60 sec or 1 min 2. 1:30 p.m. 3. 11-litre capacity container 4. 1850
5. 80 6. 336 7. 27 8. 27

Assessment Time

A. 1. (a) 2. (a) 3. (b) 4. (b) 5. (a) 6. (c) 7. (c) 8. (b)
B. 1. 224 2. Product 3. 56 C. 1. 25 2. 10 3. 5 4. 4 D. 1. (c) 2. (d)

Assessment - 1
1. (a) 2. (b) 3. (a) 4. (b) 5. (a) 6. CDXCV 7. LV 8. 1
9. 30,00,000 10. 60,00,000
11. One hundred twenty three billion four hundred fifty six million seven hundred eighty-nine thousand
12. 123456789,000
13. 1,00,00,00,00,000 + 20,00,00,00,000 + 3,00,00,00,000 + 40,00,00,000 + 5,00,00,000 + 60,00,000 + 7,00,000 + 80,000 + 9000
14. (a) 15. a 16. 5 and 50,00,000 difference 49,99,995 17. 78,728 < 85125 < 6,52,361 < 55,23,620
18. 6,78,30,208; six crore seventy eight lakh thirty thousand two hundred eight 19. 30 → 2, 3, 5; 45 → 3, 5
20. (a) 3,52,36,387 (b) Quotient = 1514, Remainder = 54 21. 80 22. (a) 25 (b) 13
23. 36 24. 480 25. 60 30 15 5

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