Page 385 - Start Up Mathematics_8 (Non CCE)

Reason It Out! 4. 10 5. 325 minutes 6. 29.17 km 7. ` 12,375
Pulkit was born on 31 December and said this on 1 January. 8. ` 1,937.50 9. 21 10. 1,500 g or 1.5 kg
Therefore, two days before, i.e., on 30 December, he was 23 11. 857.5 mm 12. 48 days 13. 6
years old. On 31 December last year, he was 24 years old. On Exercise 9.2
the 31 December of the year in which Pulkit made this state-
ment, he will be 25 years old and on 31 December of the year 1. a, b and e 2. b
after that, he will be 26 years old, making his statement true. 3. (a) 6, 9, 5, 3 (b) 24, 15, 8, 16 4. 20 days
Review Exercises 5. 12 pages 6. 60 min 7. 10 h 8. 9 kg
Multiple Choice Questions 9. 15 boxes 10. (a) 2 (b) 14 (c) 15 (d) 11
1. c 2. a 3. b 4. d 5. d Review Exercises
6. d 7. a Multiple Choice Questions
Solve Mentally 1. b 2. c 3. d 4. a 5. b
True or False
1. True 2. False 3. False 4. True 5. False Solve Mentally
Answer in One Word or a Line Fill in the Blanks
1. An equation consisting of only linear polynomials is called 1. constant, positive 2. 21 3. inverse 4. 8
a linear equation. For example, 12a + 5 = –7 Answer in One Word or a Line
2. Yes 1. Two quantities are said to be in variation, if the change
3. 4x – 6 = 2x + 8 in the measure of one results in a corresponding change
4. We cross multiply and then solve the linear equation. in the measure of the other.
5. No There are 2 types of variation—direct and inverse.
2. Yes 3. 7 days
Let’s Evaluate 4. Their product should be constant and positive.
98 11 5 - 11
1. (a) (b) (c) (d) 12 (e) (f) 2 Let’s Evaluate
91 4 2 9
2. 7, 8, 9 3. 30, 31 4. 16 years, 8 years 1. ` 7,99,920 2. 4 3. 18 km/h
5. 45 6. 120 4. 40 days 5. 2, 35, 9 and 60
Thinking Skills Thinking Skills
1. 44.8 km
1. d 2. 48 3. 9 km 2. 240 3. ` 8,400 4. 168
4. 91 42 140 77 Values and Life Skills
133 84 98 35 1. 60 L 2. 20
56 105 63 126 3. 4 4. 20 pumps
70 119 49 112
Exemplar Problems
Values and Life Skills 16 2
1. 3,000 notes of ` 50; 4,000 notes of ` 20 and 5,000 notes 1. a 2. 3 h or 5h 20 min 3. 480 cm
of ` 10. 4. False 5. 8.75 cm 6. 9 m
2. 230 passengers bought tickets of `500 each and 250
passengers bought tickets of ` 750 each. Total money paid 7. 0.6 s 8. 60 g
is ` 3,02,500. Chapter 10
3. 100 mL
Exemplar Problems Exercise
1. a 2. b 3. Solution 4. False 1. (a) 24 days (b) 5 of work is left
6
5. (a) x = 2 (b) x = –96 6. ` 4,500 7. 24 1
8. 9 km/h 2. ` 5,760 3. 30 min 4. 1 days
5
Chapter 9 5. 32 days 6. 135 7. 48 min
Exercise 9.1 1
1. a, c, d 2. a 8. 31 hours
2
3. (a) 120, 225, 300 and 375 Brainstorming
(b) 7, 13, 7.5, 18.50 and 13.25 The rabbit will take infinite jumps to cover any distance.

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