Page 337 - Start Up Mathematics_7

4. Improper fractions are those in which the numerator is Exercise 3.2
greater than or equal to the denominator. Mixed fractions 1. (a) 33.4 (b) 215.67 (c) 0.895
are a combination of a whole number and a proper
fraction. A mixed fraction and an improper fraction are 2. (a) 1,330.4 (b) 22,156.7 (c) 68.9 (d) 308.95
1 3 4 1×+ 13 3. (a) 1,23,340 (b) 256.7 (c) 5,689
interconvertible. For example, 3 = = .
4 4 4 4. (a) 49.13 (b) 237.237 (c) 49.6144 (d) 0.01615
5. The product of a proper and an improper fraction is greater
than the proper fraction and less than the improper fraction 5. (a) 3.3027 (b) 19.4403 (c) 12.0575 (d) 53.084
(assuming improper fraction is greater than 1). 6. 11.9025 m 7. 90.0375 m 2 8. ` 3,873.45
2
6. Multiplicative inverse of a fraction is its reciprocal. It Exercise 3.3
does not exist for the number 0.
7. 200 mm 1. (a) 23.456 (b) 3.478 (c) 0.00056 (d) 0.00236
2. (a) 5.34057 (b) 1.34078 (c) 0.010356 (d) 0.000059
Let’s Evaluate
3. (a) 1.23456 (b) 0.384734 (c) 0.0020056 (d) 23.598
287 145 5 3 6 2
1. (a) (b) 2. , , , 4. (a) 45.63 (b) 2.034 (c) 1.0056 (d) 3.2065
30 24 16 8 12 3
11 13 3 9 124 5. (a) 100 (b) 336.95 (c) 0.08 (d) 0.029
3. , , , 4. (a) 25 (b)
14 28 7 35 147 6. 12.64 km 7. 300 8. ` 23.05 9. 6
26 1 Group Project (Plug in the missing decimals)
5. ` 1,20,000 6. 15 7. 1 8. 9
29 2 (a) Variable answer (b) Yes, Yes, No (c) Yes, No
Thinking Skills Reason It Out!
7 1. Manually we get 0.0540 and by calculator 0.054. There
1. 6 books, 4 encyclopedias 2.
9 is no difference as we can add or delete any number of
5 5 zeros after the decimal places.
3. (a) 24 (b) 4. (a) 52 (b) m
12 14 2. (a) 1.3 , 1.6 , 1.9 (b) 5.1 , 6.3 , 7.5
(c) 6.4 , 12.8 , 25.6 (d) 0.1375 , 0.06875 , 0.034375
I (e) 3.641 , 3.64 , 3.6
II Changing Fractions to Decimals
5. I II III or III 1. (a) 0.375 (b) 0.571 (c) 0.625 (d) 0.5

Values and Life Skills 2. In figure (b) the decimal representing the shaded region is
1. 3,500 ; 2,500 2. 2 9 h non-terminating repeating, so 0.571 is an approximation.
20 Review Exercises
3. ` 29,400 4. 45
Multiple Choice Questions
Exemplar Problems
8
1. d 2. a 3. 17 or 1 4. False 1. b 2. d 3. d 4. a 5. c
9 9 6. c 7. c
5 10
5. 24 boxes 6. (i) (a) (b) (ii) 7 tonnes Solve Mentally
13 13
7. ` 300 8. 2 True or False
1. False 2. True 3. True 4. True
Chapter 3 5. False 6. False
Exercise 3.1
Fill in the Blanks
1. (a) ` 0.17 (b) ` 55.55
1. decimal 2. 14 3. 5 4. 7.63
2. (a) 0.25 m (b) 0.00135 km (c) 0.02 m (d) 0.0002 km
5. 0.00001 6. smaller
3. (a) 0.039 kg (b) 3.380 kg 7. (a) × (b) + (c) ÷ (d) –
1 1
4. (a) 1 × 10 + 2 × 10 + 7 × + 9 × Answer in One Word or a Line
0
10 100
1 1 1. 3 2. 16 or 8 3. 7,000 m
(b) 2 × 10 + 3 × 10 + 4 × 10 + 9 × + 5 × 1,000 10 5
0
1
2
10 100
5. 11.3 km 6. Reshma, 0.06 kg or 60 g 4. ` 63.45 5. ` 6 6. 2.6 L
329