Selina Chapter 4 Decimal Fractions ICSE Solutions Class 7 Maths

Selina Concise Solutions for Chapter 4 Decimal Fractions (Decimals) Class 7 ICSE Mathematics

Exercise 4 (A)

1. Convert the following into fractions in their lowest terms :
(i) 3.75
(ii) 0.5
(iii) 2.04
(iv) 0.65
(v) 2.405
(vi) 0.085
(vii) 8.025

Answer 

2. Convert into decimal fractions 

(ii) 79/100
(iii) 37/10,000
(iv) 7543/10⁴
(v) 3/4 

Answer 

3. Write the number of decimal places in :
(i) 0.4762
(ii) 7.00349
(iii) 8235.403
(iv) 35.4
(v) 2.608
(vi) 0.000879

Answer

(i) In 0.4762, there are four places.
(ii) In 7.00349, there are five places.
(iii) In 8235.403, there are three places.
(iv) In 35.4, there is one place.
(v) In 2.608, there are three places.
(vi) In 0.000879, there are six places.

4. Write the following decimals as word statements :

(i) 0.4,0.9,0.1

(ii) 1.9, 4.4, 7.5

(iii) 0.02, 0.56, 13.06

(iv) 0.005,0.207, 111.519

(v) 0.8, 0.08, 0.008, 0.0008

(vi) 256.1, 10.22, 0.634

Answer

(i) 0.4 = zero point four, 0.9 = zero point nine, 0.1 = zero point one.

(ii) 1 .9 = one point nine, 4.4 = four point four, 7.5 = seven point five.

(iii) 0.02 = zero point zero two, 0.56 = zero point five six, 13.06 = thirteen point zero six.

(iv) 0.005 = zero point zero zero five, 0.207 = zero point two zero seven, 111.519 = one

hundred eleven point five one nine.

(v) 0.8 = zero point eight, 0.08 = zero point zero eight, 0.008 = zero point zero zero

eight, 0.0008 = zero point zero zero zero eight

(vi) 256.1 = Two hundred fifty six point one, 10.22 = Ten point two two, 0.634 = zero

point six three four.

5. Convert the given fractions into like fractions:

(i) 0.5,3.62,43.987 and 232.0037

(ii) 215.78, 33.0006, 530.3 and 0.03569

Answer

(i) 0.5, 3.62, 43.987 and 232.0037

In these decimals, the greatest places of decimal is 4

∴0.5 = 0.5000

3.62 = 3.6200

43.987 = 43.9870

232.0037 = 232.0037

(ii) 215.78, 33.0006, 530.3 and 0.03569

In these decimals, the greatest places of decimal is 5

∴ 215.78 = 215.78000

33.0006 = 33.00060

530.3 = 530.30000

0.03569 = 0.03569

Exercise 4 (B)

1. Add:

(i) 0.5 and 0.37 (ii) 3.8 and 8.7

(iii) 0.02, 0.008 and 0.309

(iv) 0. 4136, 0. 3195 and 0.52

(v) 9.25, 3.4 and 6.666

(vi) 3.007, 0.587 and 18.341

(vii) 0.2, 0.02 and 2.0002

(viii) 6. 08, 60.8, 0.608 and 0.0608

(ix) 29.03, 0.0003, 0.3 and 7.2

(x) 3.4, 2.025, 9.36 and 3.6221

Answer

2. Subtract the first number from the second :

(i) 5.4, 9.8

(ii) 0.16, 4.3

(iii) 0.82, 8.6

(v) 2.237, 9.425

(vi) 41 .03, 59.46

(vii) 3.92. 26.86

(viii) 4.73, 8.5

(ix) 12.63, 36.2

(x) 0.845, 3.71

Answer 

3. Simplify :

(i) 28.796 -13.42 – 2.555

(ii) 93.354 – 62.82 – 13.045

(iii) 36 – 18.59 – 3.2

(iv) 86 + 16.95 – 3.0042

(v) 32.8 – 13 – 10.725 +3.517

(vi) 4000 – 30.51 – 753.101 – 69.43

(vii) 0.1835 + 163.2005 – 25.9 – 100

(viii) 38.00 – 30 + 200.200 – 0.230

(ix) 555.555 + 55.555 – 5.55 – 0.555

Answer 

(i) 28.796 - 13.42 -2.555
= 28.976 - (13.42 + 2.555)
= 28.796 - 15.975

= 12.821 

(ii) 93.354 - 62.82 - 13.045 
= 93.354 - (62.82 + 13.045)
= 93.354 - 75.865

= 17.489 

(iii) 36 - 18.59 - 3.2 
= 36 -(18.59 + 3.2)
= 36 - 21.79

= 14.21 

(iv) 86 + 16.95 - 3.0042
 = 102.95 - 3.0042 = 99.9458 

(v) 32.8 - 13 - 10.725 + 3.517
= (32.8 + 3.517) - (13 + 10.725)
= 36.317 - 23.725 = 12.592

(vi) 4000 - 30.51 - 753.101 - 69.43
= 4000 - (30.51 + 753.101 + 69.43)
= 4000 - 853.041

(vii) 0.1835 + 163.2005 - 25.9 - 100
= (0.1835 + 163.2005) - (25.9 + 100)
= 163.3840 - 125.9 = 37.484

(viii) 38.00 - 30 + 200.200 - 0.230

= (38.00 + 200.200) -(30 + 0.230)
= 238.200 - 30.230 
= 207.970 = 207.97

(ix) 555.555 + 55.555 - 5.55 - 0.555
= (555.555 + 55.555) - (5.55 + 0.555)
= 611.110 - 6.105 = 605.005 

4. Find the difference between 6.85 and 0.685.

Answer 

Difference between  6.85 and 0.685 
= 6.85 - 0.685

= 6.165 

5. Take out the sum of 19.38 and 56.025 then subtract it from 200.111  .
Answer 

Sum of 19.38 + 56.025 = 75.405

6. Add 13.95 and 1.003; and from the result, subtract the sum of 2.794 and 6.2  . 

Answer 

Sum of 13.95 and 1.003 
= 13.95 + 1.003  = 14.953

7. What should be added to 39.587 to give 80.375 ?

Answer 

Sum = 80.375
Given number = 39.587 
∴ The number which is to be added 
= 80.375 - 39.587 = 40.788 

8. What should be subtracted from 100 to give 19.29 ? 

Answer 

Sum = 100 
The number = 19.29
∴ The number which is to be subtracted 
= 100 - 19.29 = 80.71 

9. What is the excess of 584.29 over 213.95 ? 

Answer 

Total = 584.29
Given number = 213.95
Required difference = 584.29 - 213.95 = 370.34 

10. Evaluate : 
(i) (5.4 - 0.8) + (2.97 - 1.462)
(ii) (6.25 + 0.36) - (17.2 - 8.97)
(iii) 9.004 + (3 - 2.462)
(iv) 879.4 - (87.94 - 8.794)

Answer 

11. What is the excess of 75 over 48.29 ? 

Answer 

Excess of 75 over 48.29

12. If A = 237.98 and B = 83.47 . 
Find :
(i) A - B 
(ii) B - A . 

Answer 

(i) A - B
A = 237.98
B = 83.47
⇒ A - B = 154.51

(ii) B -A 
= 83.47 - 237.98

= -154.51

13. The cost of one kg of sugar increases from ₹28.47 to  ₹32.65. Find the increase in cost. 

Answer

Initial cost of sugar = ₹ 28.47 
Increase cost of sugar = ₹ 32.65 
∴ Increase of sugar in cost = ₹5.18 

Exercise 4 (C)

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

Answer 

(i) 0.87 × 10 = 8.7 
(ii) 2.948 × 100 = 294.8
(iii) 6.4 × 1000 = 6400
(iv) 5.8 × 4 = 23.2
(v) 16.32 × 32 = 456.96 

(vi) 5.037 × 8 = 40.296
(vii) 4.6 × 2.1 = 9.66

(viii) 0.568 × 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

Answer 

(i) 0.5 × 10 = 5,

⇒ 0.5× 100 = 50,

⇒ 0.5 × 1000 = 500

(ii) 0.112 × 10 = 1.12,

⇒ 0.112 × 100 =11.2,

⇒ 0.112 × 1000 = 112

(iii) 4.8 × 10 = 48, 

⇒ 4.8 × 100 = 480,

⇒ 4.8 × 1000 = 4800

(iv) 0.0359 × 10 = 0.359,

⇒ 0.0359 × 100 = 3.59, 

⇒ 0.0359 × 1000 = 35-9

(v) 16.27 × 10 = 162.7,

⇒ 16.27 × 100 = 1627,

⇒ 16.27 × 1000 = 16270

(vi) 234.8 × 10 = 2348,

⇒ 234.8 × 100 = 23480,

⇒ 234.8 × 1000 = 234800

3. Evaluate:

(i) 5.897 × 2.3

(ii) 0.894 × 87

(iii) 0.01 × 0.001

(iv) 0.84 × 2.2 × 4

(v) 4.75 × 0.08 × 3

(vi) 2.4 × 3.5 × 4.8

(vii) 0.8 × 1.2 × 0.25

(viii) 0.3 × 0.03 × 0.003

(ix) 12.003 × (0.2)5

Answer 

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

Answer 

(i) 54.9 ÷ 10 = 5.49 
(ii) 7.8 ÷ 100 = 0.078 
(iii) 324.76 ÷ 1000 = 0.32476
(iv) 12.8 ÷ 4 = 3.2 
(v) 27.918 ÷ 9 = 3.102
(vi) 4.672÷ 8 = 0.584

(vii) 4.32 ÷ 1.2
= 432 ÷ 120

= 3.6 

(viii) 7.644 ÷ 1.4
= 7644 ÷ 1400

=5.46 

(ix) 4.8432 ÷ 0.08
= 48432 ➗ 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
(vii) 0.848 × 3 
(viii) 4.906 × (0.2)²
(ix)  (1.2)² × (0.9)²    

Answer 

(i) 2.1 ÷ 10 = 0.21 
2.1 ÷ 100 = 0.021
2.1 ÷ 1000 = 0.0021
2.1 ÷ 10000 = 0.00021 

(ii) 8.64 ÷ 10 = 0.864

8.64 ÷100 = 0.0864
8.64 ÷ 1000 = 0.00864
8.64 ÷ 10000 = 0.000864

(iii) 5.01 ÷ 10 = 0.501,
5.01 ÷ 100 = 0.0501
5.01 ÷ 1000 = 0.00501
5.01 ÷ 10000 = 0.000501

(iv) 0.0906 ÷ 10 = 0.00906
0.0906 ÷ 100 = 0.000906 
0.0906 ÷ 1000 = 0.0000906
0.0906 ÷ 10000 = 0.00000906

(v) 0.125 ÷ 10 = 0.0125 
0.125 ÷ 100 = 0.00125
0.125 ÷ 1000 = 0.000125
0.125 ÷ 10000 = 0.0000125

(vi) 111.11 ÷ 10 = 11.111
111.11 ÷ 100 = 1.1111
111.11 ÷ 1000 = 0.11111
111.11 ÷ 10000 = 0.011111

 

(vii) 0.848 × 3 = 2.544
2.544 ÷10 = 0.2544
2.544 ÷ 100 = 0.02544
2.544 ÷ 1000 = 0.002544
2.544 ÷ 10000 = 0.0002544

(viii) 4.906 × (0.2)² = 4.906 × 0.2 × 0.2 
= 4.906 × 0.04 = 0.19624
= 0.19624 ÷ 10 = 0.019624
= 0.19624 ÷ 100 = 0.0019624
= 0.19624 ÷ 1000 = 0.00019624 
= 0.19624 ÷ 10000 = 0.000019624 

(ix) (1.2)² × (0.9)² = 1.2×1.2×0.9×0.9 = 1.44×0.81 = 1.1664
1.1664 ÷ 10 = 0.11664
1.1664 ÷ 100 = 0.011664
1.1664 ÷ 1000 = 0.0011664 
1.1664 ÷ 10000 = 0.00011664

6. Evaluate : 

(i) 9.75 ÷ 5 
(ii) 4.4064 ÷ 4 
(iii) 27.69 ÷ 30 
(iv) 19.25 ÷ 25 
(v) 20.64 ÷ 16 
(vi) 3.204 ÷ 9
(vii) 0.125 ÷ 25 
(viii) 0.14616 ÷ 72 
(ix) 0.6227 ÷ 1300
(x) 257.894 ÷ 0.169 
(xi) 6.3 ÷ (0.3)³  

Answer 

(xi) 6.3 ÷ (0.3)³

= 6.3 ÷ (0.3 × 0.3)
= 6.3 ÷ (0.09)

= 630 ÷ 09
= 630 ÷ 9

= 70 

7. Evaluate:

(i) 4.3 × 0.52 × 0.3

(ii) 3.2 × 2.5 × 0.7

(iii) 0.8 × 1.5 × 0.6

(iv) 0.3 × 0.3 × 0.3

(v) 1.2 × 1.2 × 0.4

(vi) 0.4 × 0.04 × 0.004

(vii) 0.5 × 0.6 × 0.7

(Viii) 0.5 × 0.06 × 0.007

Answer 

(i) 4.3 × 0.52 × 0.3 

(Sum of decimal places = 1 + 2+ 1 = 4) 
∴ 4.3 × 0.52 × 0.3 = 0.6708 

(ii) 3.2 × 2.5 × 0.7 

(Sum of decimal places = 1+1+1 = 3)
∴ 3.2 × 2.5 × 0.7 = 5.600 or 5.6 

(iii) 0.8 × 1.5 × 0.6 

(Sum of decimal places = 1+1+1 = 3)
∴ 0.8 × 1.5 × 0.6 = 0.720 or 0.72 

(iv) 0.3 × 0.3 × 0.3

(Sum of decimal places = 1+1+1 = 3)
∴ 0.3 × 0.3 × 0.3 = 0.027

(v)  1.2 × 1.2 × 0.4 

(vi) 0.4 × 0.04 × 0.004 

(Sum of decimal places = 1+2+3= 6)
∴ 0.4 × 0.04 × 0.004 = 0.000064

(vii) 0.5 × 0.6 × 0.7 

(Sum of decimal places = 1 + 1+ 1 = 3)
∴ 0.5 × 0.6 × 0.7 = 0.210 or 0.21 

(viii) 0.5 × 0.06 × 0.007 

(Sum of decimal places = 1+ 2+ 3 = 5) 
∴ 0.5 × 0.06 × 0.007 = 0.00021 

8. Evaluate:

(i) (0.9)²  

(ii) (0.6)² × 0.5

(iii) 0.3 × (0.5)²    

(iv) (0.4)³  

(v) (0.2)³   × 5

(vi) (0.2)³   × 0.05

Answer 

(i) (0.9)²  

⇒ 0.9 × 0.9 = 0.81

(Sum of decimal places 1 + 1= 2)

(ii) (0.6)²  ×  0.5

⇒ 0.6 ×  0.6 × 0.5

⇒ 0.36 × 0.5 = 0.180 or 0.18

(Sum of decimal places = 1 + 1 + 1 = 3)

(iii) 0.3 × (0.5)²  

⇒ 0.3 × 0.5 × 0.5

⇒ 0.3 × 0.25 = 0.075

(Sum of decimal places 1 + 1 + 1 = 3)

(iv) (0.4)³  

⇒ 0.4 × 0.4 × 0.4

⇒ 0.16 × 0.4 = 0.064

(Sum of decimal places 1 + 1 + 1 = 3)

(v) (0.2)³   × 5

⇒ 0.2 × 0.2 × 0.2 × 5

⇒ 0.08 × 5 = 0.40 or 0.4

(Sum of decimal places 1 + 1 + 1 = 3)

(vi) (0.2)³   × 0.05

⇒ 0.2 × 0.2 × 0.2 × 0.05

⇒ 0.008 × 0.05 = 0.00040

(Sum of decimal places = 5)

9. Find the cost of 36.75 kg wheat at the rate of  ₹12.80 per kg.

Answer 

Total weight of wheat  = 36.75 kg 
Cost of 1 kg of wheat = ₹ 12.80 
∴ Cost of 36.75 kg of wheat 
= 36.75 × 12.80 = ₹ 470.40

10. The cost of a pen is ₹ 56.15. Find the cost of 16 such pens. 

Answer 

Cost of one pen = ₹ 56.15 
∴ Cost of 16 pens 
= ₹ 56.15 × 16 = ₹ 898.40

11. Evaluate:

(i) 0.0072 ÷ 0.06

(ii) 0.621 ÷ 0.3

(iii) 0.0532 ÷ 0.005

(iv) 0.01162 ÷ 0.14

(v) (7.5 × 40.4) ÷ 25

(vi) 2.1 ÷ (0.1 × 0.1)

Answer 

(i)  0.0072 ÷ 0.06 

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

Answer

Weight of 15 articles = 31.50 kg

∴ Weight of one article

= 31.50- 15 = 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.

Answer

The product of two numbers = 211.2
one number = 16.5 
∴ Second number = 211.2 ÷ 16.5 
= (211.2 × 10)/(16.5×10
= 2112/165 = 12.8

14. One dozen identical articles cost ₹45.96. Find the cost of each article.

Answer

∴ Weight of one dozen articles = ₹45.96

One dozen = 12

∴ Cost of one article = 45.96 + 12 = ₹3.83

Exercise 4 (D)

1. Find whether the given division forms a terminating decimal or a non-terminating

decimal:

(i) 3 ÷ 8

(ii)8 ÷ 3

(iii) 6÷ 5

(iv) 5 ÷ 6

(v) 12.5 ÷ 4

(vi) 23 ÷ 0.7

(vii) 42 ÷ 9

(viii) 0.56 ÷ 0.11

Answer 

(i) 3 ÷ 8 = 0.375 
Hence it is terminating decimal. 

(ii) 8 ÷ 3 = 2.666....
Hence it is non - terminating decimal.

(iii) 6 ÷ 5 = 1.2 
Hence it is terminating decimal. 

(iv) 5 ÷ 6 = 0.8333.....
Hence it is non - terminating decimal .

(v) 12.5 ÷ 4 = 3.125 
Hence it is terminating decimal. 

(vi) 23 ÷ 0.7

= 230 ÷ 7

= 32.8571428.......
Hence it is non - terminating decimal. 

(vii) 42 ÷ 9 = 4.666.....
Hence it is non - terminating decimal. 

(viii) 0.56 ÷ 0.11

= 56 ÷ 11

= 5.0909.....

Hence it is non - terminating decimal . 

2. Express as recurring decimals : 

(ii) 10/11
(iii) 5/6
(iv) 2/13
(v) 1/9
(vi) 17/90
(vii) 5/18
(viii) 7/12

Answer 

3. Convert into vulgar fraction : 

(i) 0. 3

(i) 0. 8

(i) 4. 4

(i) 23. 7

Answer 

4. Convert into vulgar fraction : 

(i) 0. 35

(i) 2. 23

(i) 1. 28

(i) 5. 234

Answer 

5. Convert into vulgar fraction : 

(i) 0. 37

(i) 0. 245

(i) 0. 685

(i) 0. 442

Answer 

Exercise 4 (E)

1. Round off:

(i) 0 .07, 0.112, 3.59, 9.489 to the nearest tenths.

(ii) 0.627, 100.479, 0 065 and 0.024 to the nearest hundredths.

(iii) 4.83,0.86,451 .943 and 9.08 to the nearest whole number.

Answer 

(i) 0.07 = 0.1,

0.112 = 0.1

3.59 = 3.6,

9.489 = 9.5

(ii) 0.627 = 0.63,

100.479 = 100.48

0.065 = 0.07,

0.024 = 0.02

(iii) 4.83 = 5,

0.86= 1,

451.943 = 452

9.08 = 9

2. Simplify, and write your answers correct to the nearest hundredths :

(i) 18 .35 × 1.2

(ii) 62.89 × 0.02

Answer 

(i) 18. 32 × 1.2 = 22.02

(ii) 62.89 × 0.02 = 1.2578 = 1.26 

3. Write the number of significant figures (digits) in : 

(i) 35.06

(ii) 0.35

(iii) 7.0068

(iv) 19 .0

(v) 0.0062

(vi) 0 4.2 × 0.6

(vii) 0.08 × 25

(viii) 3.6 ÷ 0.12 .

Answer 

(i) 35.06 : In this significant figures i.e. digits are 4

(ii) In 0.35, significant figures are 2

(iii) In 7.0068, significant figures are 5

(iv) In 19.0, significant figures are 3

(v) In 0.0062, significant figures are 2

(vi) In 4.2 × 0.6 = 2.52, significant figure are 3

(vii) In 008 × 25 = 2.00 = 2 significant figure is 1

(viii) In 3.6 ÷ 0 .12 or 360 ÷ 12 = 30, significant figure are 2.

4. Write :

(i) 35.869,0 008426,4.952 and 382.7, correct lo three significant figures.

(ii) 60.974. 2.8753, 0.001789 and 400.04, correct to four significant figures.

(iii) 14.29462, 19.2, 46356.82 and 69, correct to five significant figures.

Answer

(i) Correct to three significant figures are

35.869 → 35.9

0.008426 → 0.00843

4. 952 → 4.95

382.7 →383

(ii) Correct to four significant figures

60.974 → 60.97

2. 8753 → 2.875

0.001789 → 0.001789

400.04 → 400.0

(iii) Correct to five significant figures

14.29462 → 14.295

19.2 → 19.200

46356.82 → 46357

69 → 69.000

Exercise 4 (F)

1. The weight of an object is 3 .06 kg. Find the total weight of 48 similar objects.

Answer 

Weight of one object = 3.06 kg 
∴ Weight of 48 objects  = 3.06 × 48 = 146.88 kg 

2. Find die cost of 17.5 m cloth at the rate of Rs. 112.50 per metre. 

Answer 

Cost of 1 metre cloth = Rs. 112.50
∴ Cost of 17.5 m cloth 
= Rs. 112.50 × 17.5
= Rs. 1968.750 
= 1968.75 

3.  One kilogramme of oil costs Rs. 73.40 . Find the cost of 9.75 kilogramme of the oil. 

Answer 

Cost of 1 kg oil = Rs. 73.40 
∴ Cost of 9.75 kg oil = Rs. 73.40 × 9.75
= Rs. 715.6500
= Rs. 715.65 

4. Total weight of 8 identical objects is 51.2 kg. Find the weight of each object.

Answer

Weight of 8 objects = 51.2 kg

∴ Weight of 1 object = 51.2/8 kg = 6.4 kg

5. 18.5 m of cloth costs Rs. 666. Find the cost of 3.8 m cloth.

Answer

Cost of 18.5 m cloth = Rs. 666

Cost of 1 m cloth = Rs. 666 ÷18.5 and cost of 3.8 m cloth

= Rs. (666 ÷18.5)× 3.8

= Rs. (6660 ÷ 185)× 3.8

= Rs. 36×3.8

= Rs. 136.80

6. Find die value of:

(i) 0.5 of Rs. 7.60 + 1.62 of Rs. 30

(ii) 2.3 of 7.3 kg + 0.9 of 0.48 kg

(iii) 6.25 of 8.4 – 4.7 of 3.24

(iv) 0.98 of 235 – 0 .09 of 3.2

Answer 

(i) 0.5 of  Rs. 7.60 + 1.62 of Rs. 30 
= Rs. 3.80 + Rs. 48.60
= Rs. 52.40 

(ii) 2.3 of 7.3 kg + 0.9 of 0.48 kg 
= 16.79 kg  + 0.432 kg = 17.222 kg 

(iii) 6.25 of 8.4 - 4.7 of 3.24 
= 52.500 - 15.228 = 37.272 

(iv) 0.98 of 235 - 0.09 of 3.2 = 230.30 - 0.288  = 230.012 

7. Evaluate:

(i) 5.6 – 1 .5 of 3.4

(ii) 4.8 ÷ 0.04 of 5

(iii) 0.72 of 80 + 0.2

(iv) 0.72 ÷ 80 of 0.2

(v) 6.45 + (3.9 – 1.75)

(vi) 0.12 of(0.104 – 0.02)+ 0.36×0.5

Answer 

(i) 5.6  - 1.5 of 3.4

= 5.6 - 5.1

= 5.6 - 5.1 = 0.5 

(ii) 4.8 ÷ 0.04 of 5

= 4.8 ÷ 0.20 
= 4.8 ÷ 0.2

= 48 ÷ 2

= 24 

(iii) 0.72 of 80 ÷ 0.2

= 57.60 ÷ 0.2 
= 57.6 ÷ 0.2

= 576 ÷ 2

= 288 

(iv) 0.72 ÷ 80 of 0.2

= 0.72 ÷ 16.0
= 0.72 ÷ 16

=72 ÷ 1600

(v) 6.45 ÷ (3.9 - 1.75)

= 6.45 ÷ (3.90 - 1.75)
= 6.45 ÷ 2.15

= 645 ÷ 215

= 3 

(vi) 0.12 of (0.104 - 0.02) + 0.36×0.5
= 0.12 of 0.084 + 0.36×0.5 
= 0.01008 + 0.180

= 0.19008