Selina Solutions Concise Maths Class 7 Chapter 4 Decimal Fractions (Decimals) Exercise 4C provides students with the basic knowledge of multiplication and division of decimal numbers. Students can solve the problems on a regular basis and clear their doubts by referring to the solutions PDF. The solutions are strictly according to the current syllabus and marks weightage in the annual exam. Students can boost their confidence in solving tricky problems with the help of solutions PDF. Selina Solutions Concise Maths Class 7 Chapter 4 Decimal Fractions (Decimals) Exercise 4C, PDF links are provided here.

## Selina Solutions Concise Maths Class 7 Chapter 4: Decimal Fractions (Decimals) Exercise 4C Download PDF

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**1. Multiply:**

**(i) 0.87 by 10**

**(ii) 2.948 by 100**

**(iii) 6.4 by 1000**

**(iv) 5.8 by 4**

**(v) 16.32 by 28**

**(vi) 5. 037 by 8**

**(vi) 4.6 by 2.1**

**(viii) 0.568 by 6.4**

**Solution:**

**(i) 0.87 by 10It can be written as**

**0.87 Ã— 10 = 8.7**

**(ii) 2.948 by 100It can be written as**

**2.948 Ã— 100 = 294.8**

**(iii) 6.4 by 1000It can be written as**

**6.4 Ã— 1000 = 6400**

**(iv) 5.8 by 4It can be written as**

**5.8 Ã— 4 = 23.2 **

**(v) 16.32 by 28It can be written as**

**16.32 Ã— 28 = 456.96**

**(vi) 5.037 by 8It can be written as**

**5.037 Ã— 8 = 40.296**

**(vi) 4.6 by 2.1It can be written as**

**4.6 Ã— 2.1 = 9.66**

**(viii) 0.568 by 6.4**

**It can be written as**

**0.568 Ã— 6.4 = 3.6352**

**2. Multiply each number by 10, 100, 1000: **

**(i) 0.5**

**(ii) 0.112**

**(iii) 4.8**

**(iv) 0.0359**

**(v) 16.27**

**(vi) 234.8**

**Solution:**

**(i) 0.5It can be written as**

**0.5 Ã— 10 = 5**

**0.5 Ã— 100 = 50**

**0.5 Ã— 1000 = 500**

**(ii) 0.112It can be written as**

**0.112 Ã— 10 = 1.12**

**0.112 Ã— 100 = 11.2**

**0.112 Ã— 1000 = 112**

**(iii) 4.8It can be written as**

**4.8 Ã— 10 = 48**

**4.8 Ã— 100 = 480**

**4.8 Ã— 1000 = 4800**

**(iv) 0.0359It can be written as**

**0.0359 Ã— 10 = 0.359**

**0.0359 Ã— 100 = 3.59**

**0.0359 Ã— 1000 = 35.9**

**(v) 16.27It can be written as**

**16.27 Ã— 10 = 162.7**

**16.27 Ã— 100 = 1627**

**16.27 Ã— 1000 = 16270**

**(vi) 234.8**

**It can be written as**

**234.8 Ã— 10 = 2348**

**234.8 Ã— 100 = 23480**

**234.8 Ã— 1000 = 234800**

**3. Evaluate:**

**(i) 5.897 x 2.3**

**(ii) 0.894 x 87**

**(iii) 0.01 x 0.001**

**(iv) 0.84 x 2.2 x 4**

**(v) 4.75 x 0.08 x 3**

**(vi) 2.4 x 3.5 x 4.8**

**(vii) 0.8 x 1.2 x 0.25**

**(viii) 0.3 x 0.03 x 0.003**

**Solution:**

**(i) 5.897 x 2.3We know that **

**5.897 x 2.3 = 13.5631**

**(ii) 0.894 x 87We know that**

**0.894 x 87 = 77.778**

**(iii) 0.01 x 0.001We know that**

**0.01 x 0.001 = **0.00001

**(iv) 0.84 x 2.2 x 4It can be written as**

**= 0.84 x 8.8**

**= 7.392**

**(v) 4.75 x 0.08 x 3It can be written as**

**= 4.75 x 0.24**

**= 1.1400**

**= 1.14**

**(vi) 2.4 x 3.5 x 4.8It can be written as**

**= 8.40 x 4.8**

**= 8.4 x 4.8**

**We get**

**= 40.32**

**(vii) 0.8 x 1.2 x 0.25It can be written as**

**= 0.96 x 0.25= 0.2400**

**= 0.24**

**(viii) 0.3 x 0.03 x 0.003**

**It can be written as**

**= 0.009 x 0.003**

**= 0.000027**

**4. Divide: **

**(i) 54.9 by 10**

**(ii) 7.8 by 100**

**(iii) 324.76 by 1000**

**(iv) 12.8 by 4**

**(v) 27.918 by 9**

**(vi) 4.672 by 8**

**(vii) 4.32 by 1.2**

**(viii) 7.644 by 1.4**

**(ix) 4.8432 by 0.08**

**Solution:**

**(i) 54.9 by 10It can be written as**

**54.9 **Ã· 10 = 5.49

**(ii) 7.8 by 100It can be written as**

**7.8 **Ã· 100 = 0.078

**(iii) 324.76 by 1000It can be written as**

**324.76 **Ã· 1000 = 0.32476

**(iv) 12.8 by 4It can be written as**

**12.8 **Ã· 4 = 3.2

**(v) 27.918 by 9It can be written as**

**27.918 **Ã· 9 = 3.102

**(vi) 4.672 by 8**

**It can be written as**

**4.672 **Ã· 8 = 0.584

**(vii) 4.32 by 1.2It can be written as**

**4.32 **Ã· 1.2

Multiplying by 100

432 Ã· 120 = 3.6

**(viii) 7.644 by 1.4It can be written as**

**7.644 **Ã· 1.4

Multiplying by 1000

7644 Ã· 1400 = 5.46

**(ix) 4.8432 by 0.08**

**It can be written as**

**4.8432 **Ã· 0.08

**So we get**

**48432 **Ã· 800 = 60.54

**5. Divide each of the given numbers by 10, 100, 1000 and 10000**

**(i) 2.1**

**(ii) 8.64**

**(iii) 5-01**

**(iv) 0.0906**

**(v) 0.125**

**(vi) 111.11**

**Solution:**

**(i) 2.1It can be written as**

**2.1 **Ã· 10 = 0.21

2.1 Ã· 100 = 0.021

2.1 Ã· 1000 = 0.0021

2.1 Ã· 10000 = 0.00021

**(ii) 8.64It can be written as**

**8.64 **Ã· 10 = 0.864

8.64 Ã· 100 = 0.0864

8.64 Ã· 1000 = 0.00864

8.64 Ã· 10000 = 0.000864

**(iii) 5.01It can be written as**

**5.01 **Ã· 10 = 0.501

5.01 Ã· 100 = 0.0501

5.01 Ã· 1000 = 0.00501

5.01 Ã· 10000 = 0.000501

**(iv) 0.0906It can be written as**

**0.0906 **Ã· 10 = 0.00906

0.0906 Ã· 100 = 0.000906

0.0906 Ã· 1000 = 0.0000906

0.0906 Ã· 10000 = 0.00000906

**(v) 0.125It can be written as**

**0.125 **Ã· 10 = 0.0125

0.125 Ã· 100 = 0.00125

0.125 Ã· 1000 = 0.000125

0.125 Ã· 10000 = 0.0000125

**(vi) 111.11**

**It can be written as**

**111.11 **Ã· 10 = 11.111

**111.11 **Ã· 100 = 1.1111

111.11 Ã· 1000 = 0.11111

111.11 Ã· 10000 = 0.011111

**6. Evaluate :**

**(i) 9.75 **Ã·** 5**

**(ii) 4.4064 **Ã·** 4 **

**(iii) 27.69 **Ã·** 30**

**(iv) 19.25 **Ã·** 25**

**(v) 20.64 **Ã·** 16**

**(vi) 3.204 **Ã·** 9**

**(vii) 0.125 **Ã·** 25**

**(viii) 0.14616 **Ã·** 72**

**(ix) 0.6227 **Ã·** 1300**

**(x) 257.894 **Ã·** 0.169**

**(xi) 6.3 **Ã·** (0.3)Â²**

**Solution:**

**(i) 9.75 Ã· 5We get**

**9.75 Ã· 5 = 1.95**

**(ii) 4.4064 Ã· 4 We get**

**4.4064 Ã· 4 = 1.016**

**(iii) 27.69 Ã· 30We get**

**27.69 Ã· 30 = 0.923**

**(iv) 19.25 Ã· 25We get**

**19.25 Ã· 25 = 0.77**

**(v) 20.64 Ã· 16We get**

**20.64 Ã· 16 = 1.29**

**(vi) 3.204 Ã· 9We get**

**3.204 Ã· 9 = 0.356**

**(vii) 0.125 Ã· 25We get**

**0.125 Ã· 25 = 0.005**

**(viii) 0.14616 Ã· 72We get**

**0.14616 Ã· 72 = 0.00203**

**(ix) 0.6227 Ã· 1300We get**

**0.6227 Ã· 1300 = 0.000479**

**(x) 257.894 Ã· 0.169Multiplying by 1000**

**257894 Ã· **169 = 1526

**(xi) 6.3 Ã· (0.3)Â²**

**We can write it as**

**= 6.3 **Ã·** **(0.3 Ã— 0.3)

**By further calculation**

**= 6.3 **Ã· 0.09

Multiply both sides by 100

= 630 Ã· 9 = 70

**7. Evaluate: **

**(i) 4.3 x 0.52 x 0.3**

**(ii) 3.2 x 2.5 x 0.7**

**(iii) 0.8 x 1.5 x 0.6**

**(iv) 0.3 x 0.3 x 0.3**

**(v) 1.2 x 1.2 x 0.4**

**(vi) 0.4 x 0.04 x 0.004**

**(vii) 0.5 x 0.6 x 0.7**

**(viii) 0.5 x 0.06 x 0.007**

**Solution:**

**(i) 4.3 x 0.52 x 0.3We know that**

**Here the sum of decimal places = 1 + 2 + 1 = 4**

**So we get**

**4.3 x 0.52 x 0.3 = 0.6708**

**(ii) 3.2 x 2.5 x 0.7We know that**

**Here the sum of decimal places = 1 + 1 + 1 = 3**

**So we get**

**3.2 x 2.5 x 0.7 = 5.600 or 5.6**

**(iii) 0.8 x 1.5 x 0.6We know that**

**Here the sum of decimal places = 1 + 1 + 1 = 3**

**So we get**

**0.8 x 1.5 x 0.6 **= 0.720 or 0.72

**(iv) 0.3 x 0.3 x 0.3We know that**

**Here the sum of decimal places = 1 + 1 + 1 = 3**

**So we get**

**0.3 x 0.3 x 0.3 = **0.027

**(v) 1.2 x 1.2 x 0.4We know that **

** **

**Here the sum of decimal places = 1 + 1 + 1 = 3**

**So we get**

**1.2 x 1.2 x 0.4 = 0.576**

**(vi) 0.4 x 0.04 x 0.004We know that**

**Here the sum of decimal places = 1 + 2 + 3 = 6**

**So we get**

**0.4 x 0.04 x 0.004 = 0.000064**

**(vii) 0.5 x 0.6 x 0.7**

**We know that**

**Here the sum of decimal places = 1 + 1 + 1 = 3**

**So we get**

**0.5 x 0.6 x 0.7 = 0.210 or 0.21**

**(viii) 0.5 x 0.06 x 0.007**

**We know that**

**Here the sum of decimal places = 1 + 2 + 3 = 5**

**So we get**

**0.5 x 0.06 x 0.007 = 0.00021**

**8. Evaluate: **

**(i) (0.9)Â²**

**(ii) (0.6)Â² x 0.5**

**(iii) 0.3 x (0.5)Â²**

**(iv) (0.4)Â³**

**(v) (0.2) ^{3}Â x 5**

**(vi) (0.2)**

^{3}Â x 0.05**Solution:**

**(i) (0.9)Â²It can be written as**

**0.9 x 0.9 = 0.81**

**Here the sum of decimal places is 1 + 1 = 2**

**(ii) (0.6)Â² x 0.5It can be written as**

**= 0.6 x 0.6 x 0.5**

**On further calculation**

**= 0.36 x 0.5 **

**= 0.180 or 0.18**

**Here the sum of decimal places is 1 + 1 + 1 = 3**

**(iii) 0.3 x (0.5)Â²It can be written as**

**= 0.3 x 0.5 x 0.5**

**On further calculation**

**= 0.3 x 0.25 **

**= 0.075**

**Here the sum of decimal places is 1 + 1 + 1 = 3**

**(iv) (0.4)Â³It can be written as**

**= 0.4 x 0.4 x 0.4**

**On further calculation**

**= 0.16 x 0.4 **

**= 0.064**

**Here the sum of decimal places is 1 + 1 + 1 = 3**

**(v) (0.2) ^{3}Â x 5It can be written as**

**= 0.2 x 0.2 x 0.2 x 5**

**On further calculation**

**= 0.008 x 5**

**= 0.40 or 0.4**

**Here the sum of decimal places is 1 + 1 + 1 = 3**

**(vi) (0.2) ^{3}Â x 0.05**

**It can be written as**

**= 0.2 x 0.2 x 0.2 x** 0.05

**On further calculation**

**= 0.008 x 0.05**

**= 0.00040 **

**Here the sum of decimal places is 1 + 1 + 1 + 1 + 1 = 5**

**9. Find the cost of 36.75 kg wheat at the rate of â‚¹12.80 per kg.**

**Solution:**

**It is given that**

**Weight of wheat = 36.75 kg**

**Cost of wheat per kg = â‚¹12.80**

**So the cost of 36.75 kg wheat = 36.75 x 12.80 = â‚¹470.40**

**10. The cost of a pen is â‚¹56.15. Find the cost of 16 such pens.**

**Solution:**

**It is given that**

**Cost of a pen = â‚¹56.15**

**So the cost of 16 such pens = 16 x 56.15 = â‚¹898.40**

**11. Evaluate: **

**(i) 0.0072 Ã· 0.06**

**(ii) 0.621 Ã· 0.3**

**(iii) 0.0532 Ã· 0.005**

**(iv) 0.01162 Ã· 0.14**

**(v) (7.5 x 40.4) Ã· 25**

**(vi) 2.1 Ã· (0.1 x 0.1)**

**Solution:**

**(i) 0.0072 Ã· 0.06Multiplying both numerator and denominator by 100**

**= (0.0072 x 100)/ (0.06 x 100)**

**On further calculation**

**= 0.72/6**

**= 0.12**

**(ii) 0.621 Ã· 0.3Multiplying both numerator and denominator by 10**

**= (0.621 x 10)/ (0.3 x 10)**

**On further calculation**

**= 6.21/3**

**= 2.07**

**(iii) 0.0532 Ã· 0.005Multiplying both numerator and denominator by 1000**

**= (0.0532 x 1000)/ (0.005 x 1000)**

**On further calculation**

**= 53.2/5**

**= 10.64**

**(iv) 0.01162 Ã· 0.14Multiplying both numerator and denominator by 100**

**= (0.01162 x 100)/ (0.14 x 100)**

**On further calculation**

**= 1.162/14**

**= 0.083**

**(v) (7.5 x 40.4) Ã· 25It can be written as**

**= 303/25**

**= 12.12**

**(vi) 2.1 Ã· (0.1 x 0.1)**

**Multiplying both numerator and denominator by 100**

**= (2.1 x 100)/ (0.01 x 100)**

**On further calculation**

**= 210/1**

**= 210**

**12. Fifteen identical articles weigh 31.50 kg. Find the weight of each article.**

**Solution:**

**It is given that**

**Total weight of 15 identical articles = 31.50 kg**

**So the weight of each article = 31.50 â€“ 15 = 2.1 kg**

**Hence, the weight of each article is 2.1 kg.**

**13. The product of two numbers is 211.2. If one of these two numbers is 16.5, find the other number.**

**Solution:**

**It is given that**

**Product of two numbers = 211.2**

**One of the two numbers = 16.5**

**So the other number = 211.2 Ã· 16.5**

**On further calculation**

**= (211.2 x 10)/ (16.5 x 10)**

**So we get**

**= 2112/165**

**= 12.8**

**14. One dozen identical articles cost â‚¹45.96. Find the cost of each article.**

**Solution:**

**It is given that**

**Cost of one dozen articles = â‚¹45.96**

**We know that one dozen = 12**

**So the cost of one article = 45.96 Ã· 12 = â‚¹3.83**