Page 234 - Maths Skills - 8

232 Maths

Exercise - 11.1

1. (i) 352 cm (ii) 133 cm (iii) 121 m 2 (iv) 9000 m 2 (v) 577.5 cm 2 2. 21 cm 3. 346.89 m 2
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2
2
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4. 8.4 mm 5. 121 cm 6. 22 cm 7. 140.6 mm 8. 300 cm 9. 288 m ,672 m , ` 5760
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10. Total Area = 48 m (i) 12 m (ii) 10.5 m (iii) 15 m (iv) 4.5 m 11. (i) 148.5 cm 2 (ii) 360 cm 2
(iii) 60 m 12. 30 cm , 13 cm 13. 301.76 m 14. Cuboid, 1624 cm 15. 24 cm , 5 cm
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2
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16. 16800 m 17. (i) 7 cm (ii) 115 cm 18. (i) 9210 m (ii) 2800 m 2
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2
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2
Exercise - 11.2
1. (i) 1014 cm , 676 cm (ii) 294 m , 196 m 2 (iii) 30.375 m , 20.25 m 2 (iv) 726 m , 484 m 2
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2. (i) 11.875 m 2 (ii) ` 47.50 3. 10 bricks 4. 5200 cm , 2800 cm 2 5. 1944 cm , 1296 cm 2
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6. 40 cm, 30 cm, 20 cm 7. 93 m 8. (i) 222 cm , 96 cm (ii) 382 cm , 252 cm 9. ` 6864
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10. (i) 350 cm (ii) 200 cm 11. ` 1425 12. 384 cm 13. ` 25000
Exercise - 11.3
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1. (i) 125 cm 3 (ii) 274.625 cm (iii) 2744 cm (iv) 1.728 m 3 2. length = 25 cm ; breadth = 15 cm ; height = 10 cm
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3. 30 cm 4. 2.5 m 5. 5 m 6. 250 cm 7. 5400 soaps 8. 4500 litres
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9. 216 cubes 10. 810000 cm 11. 17.010 kg 12. (i) 630 cm (ii) 48300 cm 13. 90
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3
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14. 125 15. 4 cm 16. 1600000 litres 17. (breadth) units 18. ` 1800
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3
Exercise - 11.4
1. 1540 m 2. 10.5 cm 3. (i) 1650 cm ; 660 cm ; 817.14 cm (ii) 7947.5 cm ; 1870 cm ; 2324.14 cm 2
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(iii) 1810.28 cm ; 301.71 cm ; 1206.85 cm 4. 42 cm 5. 147840 cm 3 6. 28 cm 7. 3080 cm 8. 704 m 3
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9. 3696 grams 10. 1848 cm 11. 30.8 m 12. ` 422.40 13. 808.5 m 3
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Assessment Time
A. 1. (i) 2. (iii) 3. (iii) 4. (iii) 5. (ii) 6. (i) 7. (ii) 8. (iii) 9. (i) 10. (iv)
B. 1. (side) 2. square unit 3. 100 4. 1 5. two 6. length × breadth × height 7. (side) 3
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100
8. total surface area 9. 1000 10. 2πr (r + h) sq. unit C. 1. True 2. False 3. True
4. False 5. False 6. True 7. False 8. False 9. False 10. True
D. 1. (iv) 2. (ii) 3. (ii) 4. (ii) E. 1. (c) 2. (b)
F. 1. 0.25 m 2. 24 cm 3. ` 292.50 4. 201.5 m , ` 2088 5. 4928 m , 14 m 6. 3168 m 2
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2
HOTS
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1. 0.215 cm [Hint: Area of each sector = πr ] 2. 60 cm
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2
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Chapter - 12: Data Handling
Boot-up
A. 1. (ii) 2. (iii) 3. (iii) 4. (i) B. 1. range 2. mode 3. median 4. minimum
C. 1. T 2. T 3. F 4. T