English

NCERT Exemplar solutions for Mathematics [English] Class 7 chapter 11 - Exponents and Powers [Latest edition]

Advertisements

Chapters

NCERT Exemplar solutions for Mathematics [English] Class 7 chapter 11 - Exponents and Powers - Shaalaa.com
Advertisements

Solutions for Chapter 11: Exponents and Powers

Below listed, you can find solutions for Chapter 11 of CBSE NCERT Exemplar for Mathematics [English] Class 7.


Exercise
Exercise [Pages 337 - 352]

NCERT Exemplar solutions for Mathematics [English] Class 7 11 Exponents and Powers Exercise [Pages 337 - 352]

There are four options, out of which one is correct. Write the correct one.

Exercise | Q 1. | Page 337

[(–3)2]3 is equal to ______.

  • (–3)8

  • (–3)6

  • (–3)5

  • (–3)23

Exercise | Q 2. | Page 337

For a non-zero rational number x, x8 ÷ x2 is equal to ______.

  • x4

  • x6 

  • x10

  • x16

Exercise | Q 3. | Page 337

x is a non-zero rational number. Product of the square of x with the cube of x is equal to the ______.

  • second power of x

  • third power of x

  • fifth power of x

  • sixth power of x

Exercise | Q 4. | Page 338

For any two non-zero rational numbers x and y, x5 ÷ y5 is equal to ______.

  • (x ÷ y)1

  • (x ÷ y)0

  • (x ÷ y)5

  • (x ÷ y)10

Exercise | Q 5. | Page 338

am × a is equal to ______.

  • (a2)mn

  • am-n

  • am+n

  • amn

Exercise | Q 6. | Page 338

(10 + 20 + 30) is equal to ______.

  • 0

  • 1

  • 3

  • 6

Exercise | Q 7. | Page 338

The value of `(10^22 + 10^20)/10^20` is ______.

  • 10

  • 1042

  • 101

  • 1022

Exercise | Q 8. | Page 338

The standard form of the number 12345 is ______.

  • 1234.5 × 101

  • 123.45 × 102

  • 12.345 × 103  

  • 1.2345 × 104

Exercise | Q 9. | Page 338

If 21998 – 21997 – 21996 + 21995 = k.21995, then the value of k is ______.

  • 1

  • 2

  • 3

  • 4

Exercise | Q 10. | Page 338

Which of the following is equal to 1?

  • 20 + 30 + 40 

  • 20 × 30 × 40

  • (30 – 20) × 40  

  • (30 – 20) × (30 + 20)

Exercise | Q 11. | Page 338

In standard form, the number 72105.4 is written as 7.21054 × 10n, where n is equal to ______.

  • 2

  • 3

  • 4

  • 5

Exercise | Q 12. | Page 338

Square of `(-2/3)` is ______.

  • `(-2)/3`

  • `2/3`

  • `(-4)/9`

  • `4/9`

Exercise | Q 13. | Page 339

The cube `((-1)/4)` is ______.

  • `(-1)/12`

  • `1/16`

  • `(-1)/64`

  • `1/64`

Exercise | Q 14. | Page 339

Which of the following is not equal to `((-5)/4)^4`?

  • `(-5)^4/4^4`

  • `5^4/(-4)^4`

  • `- 5^4/4^4`

  • `(-5/4) xx (-5/4) xx (-5/4) xx (-5/4)`

Exercise | Q 15. | Page 339

Which of the following is not equal to 1?

  • `(2^3 xx 3^2)/(4 xx 18)`

  • `[(-2)^3 xx (-2)^4] ÷ (-2)^7`

  • `(3^0 xx 5^3)/(5 xx 25)`

  • `2^4/(7^0 + 3^0)^3`

Exercise | Q 16. | Page 339

`(2/3)^3 xx (5/7)^3` is equal to ______.

  • `(2/3 xx 5/7)^9`

  • `(2/3 xx 5/7)^6`

  • `(2/3 xx 5/7)^3`

  • `(2/3 xx 5/7)^0`

Exercise | Q 17. | Page 339

In standard form, the number 829030000 is written as K × 108, where K is equal to ______.

  • 82903

  • 829.03

  • 82.903

  • 8.2903

Exercise | Q 18. | Page 340

Which of the following has the largest value?

  1. 0.0001
  2. `1/10000`
  3. `1/10^6`
  4. `1/10^6 ÷ 0.1`
Exercise | Q 19. | Page 340

In standard form 72 crore is written as ______.

  • 72 × 107

  • 72 × 108  

  • 7.2 × 108  

  • 7.2 × 107

Exercise | Q 20. | Page 340

For non-zero numbers a and b, `(a/b)^m ÷ (a/b)^n`, where m > n, is equal to ______.

  • `(a/b)^(mn)`

  • `(a/b)^(m+n)`

  • `(a/b)^(m-n)`

  • `((a/b)^m)^n`

Exercise | Q 21. | Page 340

Which of the following is not true?

  • 32 > 23

  • 43 = 26   

  • 33 = 9 

  • 25 > 52

Exercise | Q 22. | Page 340

Which power of 8 is equal to 26?

  • 3

  • 2

  • 1

  • 4

Fill in the blanks to make the statements true.

Exercise | Q 23. | Page 340

`(-2)^31 xx (-2)^13 = (-2)^-`.

Exercise | Q 24. | Page 340

`(-3)^8 ÷ (-3)^5 = (-3)^-`.

Exercise | Q 25. | Page 340

`(11/15)^4 xx (_)^5 = (11/15)^9`

Exercise | Q 26. | Page 340

`((-1)/4)^3 xx ((-1)/4)^- = ((-1)/4)^11`

Exercise | Q 27. | Page 341

`[(7/11)^3]^4 = (7/11)^-`

Exercise | Q 28. | Page 341

`(6/13)^10 ÷ [(6/13)^5]^2 = (6/13)^-`

Exercise | Q 29. | Page 341

`[((-1)/4)^16]^2 = ((-1)/4)^-`

Exercise | Q 30. | Page 341

`(13/14)^5 ÷ (_)^2 = (13/14)^3`

Exercise | Q 31. | Page 341

`a^6 xx a^5 xx a^0 = a^-`

Exercise | Q 32. | Page 341

1 lakh = `10^-`.

Exercise | Q 33. | Page 341

1 million = `10^-`

Exercise | Q 34. | Page 341

729 = 3

Exercise | Q 35. | Page 341

432 = 24 × 3

Exercise | Q 36. | Page 341

53700000 = ______ × 107

Exercise | Q 37. | Page 341

88880000000 = ______ × 1010

Exercise | Q 38. | Page 341

27500000 = 2.75 × 10

Exercise | Q 39. | Page 341

340900000 = 3.409 × 10

Exercise | Q 40. (a) | Page 341

Fill in the blanks with <, > or = sign

32 ______ 15

  • <

  • >

  • =

Exercise | Q 40. (b) | Page 341

Fill in the blanks with <, > or = sign.

23 ______ 32

  • <

  • >

  • =

Exercise | Q 40 (c) | Page 341

Fill in the blanks with <, > or = sign.

74 ______ 54

  • <

  • >

  • =

Exercise | Q 40. (d) | Page 341

Fill in the blanks with <, > or = sign.

10,000 ______105

  • <

  • >

  • =

Exercise | Q 40. (e) | Page 341

Fill in the blanks with <, > or = sign.

63 ______ 44

  • <

  • >

  • =

State whether the given statements are True or False.

Exercise | Q 41. | Page 341

One million = 107

  • True

  • False

Exercise | Q 42. | Page 341

One hour = 602 seconds

  • True

  • False

Exercise | Q 43. | Page 341

10 × 01 = 1

  • True

  • False

Exercise | Q 44. | Page 341

(–3)4 = –12

  • True

  • False

Exercise | Q 45. | Page 341

34 > 43

  • True

  • False

Exercise | Q 46. | Page 341

`((-3)/5)^100 = (-3^100)/(-5^100)`

  • True

  • False

Exercise | Q 47. | Page 341

(10 + 10)10 = 1010 + 1010

  • True

  • False

Exercise | Q 48. | Page 341

x0 × x0 = x0 ÷ x0 is true for all non-zero values of x.

  • True

  • False

Exercise | Q 49. | Page 342

In the standard form, a large number can be expressed as a decimal number between 0 and 1, multiplied by a power of 10.

  • True

  • False

Exercise | Q 50. | Page 342

42 is greater than 24.

  • True

  • False

Exercise | Q 51. | Page 342

xm + xm = x2m, where x is a non-zero rational number and m is a positive integer.

  • True

  • False

Exercise | Q 52. | Page 342

xm × ym = (x × y)2m, where x and y are non-zero rational numbers and m is a positive integer.

  • True

  • False

Exercise | Q 53. | Page 342

xm ÷ ym = (x ÷ y)m, where x and y are non-zero rational numbers and m is a positive integer.

  • True

  • False

Exercise | Q 54. | Page 342

xm × xn = xm+n, where x is a non-zero rational number and m, n are positive integers.

  • True

  • False

Exercise | Q 55. | Page 342

49 is greater than 163.

  • True

  • False

Exercise | Q 56. | Page 342

`(2/5)^3 ÷ (5/2)^3` = 1

  • True

  • False

Exercise | Q 57. | Page 342

`(4/3)^5 xx (5/7)^5 = (4/3 + 5/7)^5`

  • True

  • False

Exercise | Q 58. | Page 342

`(5/8)^9 ÷ (5/8)^4 = (5/8)^4`

  • True

  • False

Exercise | Q 59. | Page 342

`(7/3)^2 xx (7/3)^5 = (7/3)^10`

  • True

  • False

Exercise | Q 60. | Page 342

50 × 250 × 1250 = (50)6

  • True

  • False

Exercise | Q 61. | Page 343

876543 = 8 × 105 + 7 × 104 + 6 × 103 + 5 × 102 + 4 × 101 + 3 × 100

  • True

  • False

Exercise | Q 62. | Page 343

600060 = 6 × 105 + 6 × 102

  • True

  • False

Exercise | Q 63. | Page 343

4 × 105 + 3 × 104 + 2 × 103 + 1 × 100 = 432010

  • True

  • False

Exercise | Q 64. | Page 343

8 × 106 + 2 × 104 + 5 × 102 + 9 × 100 = 8020509

  • True

  • False

Exercise | Q 65. | Page 343

40 + 50 + 60 = (4 + 5 + 6)0

  • True

  • False

Exercise | Q 66. | Page 343

Arrange in ascending order:

25, 33, 23 × 2, (33)2, 35, 40, 23 × 31

Exercise | Q 67. | Page 343

Arrange in descending order:

22+3, (22)3, 2 × 22, `3^5/3^2`, 32 × 30, 23 × 52

Exercise | Q 68. | Page 343

By what number should (–4)5 be divided so that the quotient may be equal to (–4)3

Exercise | Q 69. | Page 343

Find m so that `(2/9)^3 xx (2/9)^6 = (2/9)^(2m - 1)`

Exercise | Q 70. | Page 343

If `p/q = (3/2)^2 ÷ (9/4)^0`, find the value of `(p/q)^3`.

Exercise | Q 71. | Page 343

Find the reciprocal of the rational number `(1/2)^2 ÷ (2/3)^3`

Exercise | Q 72. (a) | Page 343

Find the value of:

70

Exercise | Q 72. (b) | Page 343

Find the value of:

77 ÷ 77

Exercise | Q 72. (c) | Page 343

Find the value of:

`(–7)^(2 xx 7 - 6 - 8)`

Exercise | Q 72. (d) | Page 343

Find the value of:

(20 + 30 + 40) (40 – 30 – 20)

Exercise | Q 72. (e) | Page 343

Find the value of:

2 × 3 × 4 ÷ 20 × 30 × 40

Exercise | Q 72. (f) | Page 343

Find the value of:

(80 – 20) × (80 + 20)

Exercise | Q 73. | Page 344

Find the value of n, where n is an integer and 2n–5 × 62n–4 = `1/(12^4 xx 2)`.

Exercise | Q 74. (a) | Page 344

Express the following in usual form:

8.01 × 107

Exercise | Q 74. (b) | Page 344

Express the following in usual form:

1.75 × 10–3

Exercise | Q 75. (a) | Page 344

Find the value of 25.

Exercise | Q 75. (b) | Page 344

Find the value of (–35).

Exercise | Q 75. (c) | Page 344

Find the value of –(–4)4.

Exercise | Q 76. (a) | Page 344

Express the following in exponential form:

3 × 3 × 3 × a × a × a × a

Exercise | Q 76. (b) | Page 344

Express the following in exponential form:

a × a × b × b × b × c × c × c × c

Exercise | Q 76. (c) | Page 344

Express the following in exponential form:

s × s × t × t × s × s × t

Exercise | Q 77. | Page 344

How many times of 30 must be added together to get a sum equal to 307?

Exercise | Q 78. (a) | Page 344

Express the following numbers using exponential notations:

1024

Exercise | Q 78. (b) | Page 344

Express the following numbers using exponential notations:

1029

Exercise | Q 78. (c) | Page 344

Express the following numbers using exponential notations:

`144/875`

Exercise | Q 79. (a) | Page 344

Identify the greater number in the following:

26 or 62

Exercise | Q 79. (b) | Page 344

Identify the greater number in the following:

29 or 92

Exercise | Q 79. (c) | Page 344

Identify the greater number in the following: 

7.9 × 104 or 5.28 × 105

Exercise | Q 80. (a) | Page 345

Express the following as a product of powers of their prime factors:

9000

Exercise | Q 80. (b) | Page 345

Express the following as a product of powers of their prime factors:

2025

Exercise | Q 80. (c) | Page 345

Express the following as a product of powers of their prime factors:

800

Exercise | Q 81. (a) | Page 345

Express the following in single exponential form:

23 × 33

Exercise | Q 81. (b) | Page 345

Express the following in single exponential form:

24 × 42

Exercise | Q 81. (c) | Page 345

Express the following in single exponential form:

52 × 72

Exercise | Q 81. (d) | Page 345

Express the following in single exponential form:

(–5)5 × (–5)

Exercise | Q 81. (e) | Page 345

Express the following in single exponential form:

(–3)3 × (–10)3

Exercise | Q 81. (f) | Page 345

Express the following in single exponential form:

(–11)2 × (–2)2

Exercise | Q 82. (a) | Page 345

Express the following numbers in standard form:

76,47,000

Exercise | Q 82. (b) | Page 345

Express the following numbers in standard form:

8,19,00,000

Exercise | Q 82. (c) | Page 345

Express the following numbers in standard form:

5, 83,00,00,00,000

Exercise | Q 82. (d) | Page 345

Express the following numbers in standard form:

24 billion

Exercise | Q 83. | Page 345

The speed of light in vaccum is 3 × 108 m/s. Sunlight takes about 8 minutes to reach the earth. Express distance of Sun from Earth in standard form.

Exercise | Q 84. (a) | Page 345

Simplify and express the following in exponential form:

`[(3/7)^4 xx (3/7)^5] ÷ (3/7)^7`

Exercise | Q 84. (b) | Page 345

Simplify and express the following in exponential form:

`[(7/11)^5 ÷ (7/11)^2] xx (7/11)^2`

Exercise | Q 84. (c) | Page 345

Simplify and express the following in exponential form:

(37 ÷ 35)4

Exercise | Q 84. (d) | Page 345

Simplify and express the following in exponential form:

`(a^6/a^4) xx a^5 xx a^0`

Exercise | Q 84. (e) | Page 345

Simplify and express the following in exponential form:

`[(3/5)^3 xx (3/5)^8] ÷ [(3/5)^2 xx (3/5)^4]`

Exercise | Q 84. (f) | Page 345

Simplify and express the following in exponential form:

(515 ÷ 510) × 55

Exercise | Q 85. (a) | Page 346

Evaluate:

`(7^8 xx a^10b^7c^12)/(7^6 xx a^8b^4c^12)`

Exercise | Q 85. (b) | Page 346

Evaluate:

`(5^4 xx 7^4 xx 2^7)/(8 xx 49 xx 5^3)`

Exercise | Q 85. (c) | Page 346

Evaluate:

`(125 xx 5^2 xx a^7)/(10^3 xx a^4)`

Exercise | Q 85. (d) | Page 346

Evaluate:

`(3^4 xx 12^3 xx 36)/(2^5 xx 6^3)`

Exercise | Q 85. (e) | Page 346

Evaluate:

`((6 xx 10)/(2^2 xx 5^3))^2 xx 25/27`

Exercise | Q 85. (f) | Page 346

Evaluate:

`(15^4 xx 18^3)/(3^3 xx 5^2 xx 12^2)`

Exercise | Q 85. (g) | Page 346

Evaluate:

`(6^4 xx 9^2 xx 25^3)/(3^2 xx 4^2 xx 15^6)`

Exercise | Q 86. | Page 347

Express the given information in Scientific notation (standard form) and then arrange them in ascending order of their size.

Sl.No. Deserts of the World Area (Sq. Kilometres)
1. Kalahari, South Africa 932,400
2. Thar, India 199,430
3. Gibson, Australia 155,400
4. Great Victoria, Australia 647,500
5. Sahara, North Africa 8,598,800
Exercise | Q 87. | Page 348

Express the given information in Scientific notation and then arrange them in descending order of their size.

SI.No. Name of the Planet Mass (in kg)
1. Mercury 330000000000000000000000
2. Venus 4870000000000000000000000
3. Earth 5980000000000000000000000
4. Mars 642000000000000000000000
5. Jupiter 1900000000000000000000000000
6. Saturn 569000000000000000000000000
7. Uranus 86900000000000000000000000
8. Neptune 102000000000000000000000000
9. Pluto 13100000000000000000000
Exercise | Q 88. | Page 349

Write the number of seconds in scientific notation.

Sl. No. Unit Value in Seconds
1. 1 Minute 60
2. 1 Hour 3,600
3. 1 Day 86,400
4. 1 Month 2,600,000
5. 1 Year 32,000,000
6. 10 Years 3,20,000,000
Exercise | Q 89. | Page 349

In our own planet Earth, 361,419,000 square kilometre of area is covered with water and 148,647,000 square kilometre of area is covered by land. Find the approximate ratio of area covered with water to area covered by land by converting these numbers into scientific notation.

Exercise | Q 90. | Page 350

If 2n+2 – 2n+1 + 2n = c × 2n, find the value of c.

Exercise | Q 91. | Page 350

A light year is the distance that light can travel in one year. 1 light year = 9,460,000,000,000 km.

  1. Express one light year in scientific notation.
  2. The average distance between Earth and Sun is 1.496 × 108 km. Is the distance between Earth and the Sun greater than, less than or equal to one light year?

Geometry Application:

Exercise | Q 92. | Page 350

The number of diagonals of an n-sided figure is `1/2(n^2 - 3n)`. Use the formula to find the number of diagonals for a 6-sided figure (hexagon).

Life science:

Exercise | Q 93. | Page 350

Bacteria can divide in every 20 minutes. So 1 bacterium can multiply to 2 in 20 minutes. 4 in 40 minutes, and so on. How many bacteria will there be in 6 hours? Write your answer using exponents, and then evaluate.


Most bacteria reproduce by a type of simple cell division known as binary fission. Each species reproduce best at a specific temperature and moisture level.

Blubber

Exercise | Q 94. | Page 352

Makes up 27 per cent of a blue whale’s body weight. Deepak found the average weight of blue whales and used it to calculate the average weight of their blubber. He wrote the amount as 22 × 32 × 5 × 17 kg. Evaluate this amount.

Life Science Application:

Exercise | Q 95. | Page 352

The major components of human blood are red blood cells, white blood cells, platelets and plasma. A typical red blood cell has a diameter of approximately 7 × 10–6 metres. A typical platelet has a diameter of approximately 2.33 × 10–6 metre. Which has a greater diameter, a red blood cell or a platelet?

Exercise | Q 96. | Page 352

A googol is the number 1 followed by 100 zeroes.

  1. How is a googol written as a power?
  2. How is a googol times a googol written as a power?

What’s the error?

Exercise | Q 97. | Page 352

A student said that `3^5/9^5` is the same as `1/3`. What mistake has the student made?

Solutions for 11: Exponents and Powers

Exercise
NCERT Exemplar solutions for Mathematics [English] Class 7 chapter 11 - Exponents and Powers - Shaalaa.com

NCERT Exemplar solutions for Mathematics [English] Class 7 chapter 11 - Exponents and Powers

Shaalaa.com has the CBSE Mathematics Mathematics [English] Class 7 CBSE solutions in a manner that help students grasp basic concepts better and faster. The detailed, step-by-step solutions will help you understand the concepts better and clarify any confusion. NCERT Exemplar solutions for Mathematics Mathematics [English] Class 7 CBSE 11 (Exponents and Powers) include all questions with answers and detailed explanations. This will clear students' doubts about questions and improve their application skills while preparing for board exams.

Further, we at Shaalaa.com provide such solutions so students can prepare for written exams. NCERT Exemplar textbook solutions can be a core help for self-study and provide excellent self-help guidance for students.

Concepts covered in Mathematics [English] Class 7 chapter 11 Exponents and Powers are Concept of Exponents, Multiplying Powers with the Same Base, Dividing Powers with the Same Base, Taking Power of a Power, Multiplying Powers with Different Base and Same Exponents, Dividing Powers with Different Base and Same Exponents, Miscellaneous Examples Using the Laws of Exponents, Decimal Number System Using Exponents and Powers, Crores, Numbers with Exponent Zero, One, Negative Exponents.

Using NCERT Exemplar Mathematics [English] Class 7 solutions Exponents and Powers exercise by students is an easy way to prepare for the exams, as they involve solutions arranged chapter-wise and also page-wise. The questions involved in NCERT Exemplar Solutions are essential questions that can be asked in the final exam. Maximum CBSE Mathematics [English] Class 7 students prefer NCERT Exemplar Textbook Solutions to score more in exams.

Get the free view of Chapter 11, Exponents and Powers Mathematics [English] Class 7 additional questions for Mathematics Mathematics [English] Class 7 CBSE, and you can use Shaalaa.com to keep it handy for your exam preparation.

Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×