# Mathsight Class 7 Solutions Chapter 5 Exponents and Powers

## Mathsight Class 7 Solutions Chapter 5

Welcome to NCTB Solutions. Here with this post we are going to help 7th class students to solve MathSight Class 7 Mathematics Book, Chapter 5, Exponents and Powers. Here students can easily get all the exercise questions solution for Chapter 5, Exponents and Powers Exercise 5.1, 5.2 and 5.3

Exponents and Powers exercise 5.1 solution :

Question no – (1)

Solution :

Correct option – (a)

The exponent is 3 is not correct about 6

Question no – (2)

Solution :

 Base Exponent (a) (-4) ⁶ 4- 6 (b) (8/9) ² 8/9 2 (c) (17)⁴ 17 4 (d) (-2/3)⁴ 2/3 4 (e) (7/17)⁷ 7/17 7

Question no – (3)

Solution :

(a) (-2)⁴

(b) -4³y²

(c) p³ q² r

(d) a²(-b)² c

(e) (-4/3)³

(f) (-3/7)³

(g) 1/5³

(h) (9/100)²

(i) (-1/10)³

Question no – (4)

Solution :

(a) a³ b² c⁵

= a × a × a × b × b × c × c × c × c × c

(b) h²y³z

= x × x × y × y × y × z

(c) p²q³

= p × p × q × q × q

(d) (3/4)²

= 3/4 × 3/4

(e) (-9) ³

=-9 × -9 × -9

Question no – (5)

Solution :

(a) 6³ = 6 × 6 × 6

= 216

(b) 12² = 12 × 12

= 144

(c) (-11/12)²

= -11/12 × -11/12

= 121/144

(d) (-3/5)³

= -3/5 × -3/5 × -3/5

= -27/125

(e) (5/-7)²

= 5/-7 × 5/-7

= 25/49

Question no – (6)

Solution :

(a) (-2)⁴ , (-3)³

= 16 > -27

(b) 7³, (6)⁴

= 343 < 1296

(c) 4² , 2⁴

= 16

= 16

(d) 10² , 5⁴

= 100 < 625

(e) 5², 2⁵

= 25 < 32

Question no – (7)

Solution :

(a) 7 + 3 × 2³

= 7 + 3 × 8

= 7 + 24

= 31

(b) 5 + 7 × (-3)²

= 5 + 7 × 9

= 5 + 63

= 68

(c) (13² – 12²)/5

= (169 -144) ÷ 5

= 25 ÷ 5

= 5

(d) 1/2 (4³ – 6 × 3²) = 1/2 (64 – 6 × 9)

= 1/2 (64 – 63)

= 1/2 × 1

= 1/2

(e) |1/4 (7 + 5²)| = |1/5 (7 + 25)|

= |1/5 × 32

= | |32/5|

(f) [ (-1/2)³ ÷ -1/4)² = -1/8 ÷ 1/16

= -1/8 × 16/1

= -2

Question no – (8)

Solution :

2500 = (50 × 50)

= (50)²

Question no – (9)

Solution :

2⁴ = 4²

∴ 4,2

Question no – (10)

Solution :

 1 2 3 4 5 2n-1 1 3 7 15 31 2n-1 1 2 4 8 16

She choose 2n-1

Question no – (11)

Solution :

2⁶ = 64

8² = 64

Exponents and Powers exercise 5.2 solution :

Question no – (1)

Solution :

(a) (-10)⁷ / (-10)²

Question no – (2)

Solution :

Correct option – (c)

write 1/4 cubed as a power is different from all.

Question no – (3)

Solution :

(a) 17-³ = 1/17³

= 1/4913

(b) 4⁷/4⁴ = 4⁷-11

= 4-4  = 1/44

= 1/256

(c) a⁴ × a-⁶

= a-24

= 1/a24

(d) (4-⁶)

= 4-12

= 1/412

= 16, 777, 216

(e) (1/5-²)

= 52

= 5 × 5

= 25

Question no – (4)

Solution :

(a) y2 × y3/y4 = y5-4

= y = 1/y-1

(b) 3/y

= (y/3)-1

(c) 2/3

= (3/2)-1

(d) 53/54

= 5-1

(e) 1/24

= 2-4

Question no – (5)

Solution :

(a) 82 × 83 = 85

= 20,480

(b) (-3)5 × (-3)3

= -243 × -27

= 6,561

(c) m× m7 = m11

(d) (2x)3 × (2x)4

= 8x3 × 16x4

= 128x7

(e) [(-4)2]3

= -46

= 4,096

(f) (3x0)3 = 33.13 = 27

(g) [(-4)3]3 = -y9

(h) (23y3)-2 = 26 y-6

= 64y-6

(i) 510÷58 = 510-8

= 52

(j) (-7)7÷ (-7)2 = 79

(k) y6÷y12

= y6-12

= y-6

(l) (44)5÷220

= 420/220

= (4/2)20

= 220

= 104

= 8576

(m) (4/x2)3

= 43/x6

= 64/x6

(n) (-y/n4)4

= y4/n16

Question no – (6)

Solution :

(a) 7×62 = (42)2

= 1764

(b) (-4)3 × 53 = (-20)3

= -8000

(c) a5 ×d5 = a5b5

(d) (4y)2 × (3z)2

= (12)2 y2z2

= 144y2z2

(e) 4× 44 /4

= 4 × 44

= 45

= 1024

(f) c8/c× c12/c7

= c2 × c5

= c7

(g) (-7)× 32

= 49 × 9

= 441

(h) (-12)2 × (-4)3

= 144 × (-64)

= -9216

(i) (-2)3 ×32 × 5

= 27 × 9 × 65

= -1215

(j) 7× 22 × (-5)2

= 49 × 4 × 25

= 4900

(k) 42 × (-5)3 × 3

= 16 × (-125) × 3

= 6000

(l) 4 × 5 × 202

= 20 × 400

= 8000

Question no – (7)

Solution :

(a) 50 + 70 = 1+1

= 2

(b) [(-3/5)3]2

= -36/56

= -729/15625

(c) (60+17) ÷ 25

= (1+17) ÷ 3125

=18/3125

(d) (4-1 + 5-1) ÷ 32

= (1/4 + 1/5) ÷ 9

= 5 + 4/20 × 9

= 9/20 × 9

= 1/20

(e) [(-1)3]= -118

= 1

(f) [(3/4)2]÷ [(3/4)4]2

= (3/4)÷ (3/4)8

= 1

Question no – (8)

Solution :

(a) (-2/5)8 × (-2/5)4 = (-2/5)x-1

Or, (-2/5)x-1

= (-2/5)8+4

= (-2/5)12

Or, x – 1

= 12

Or, x

= 12 + 1

=13

(b) (5/9)12  ÷ (5/9)x

= 125/729

Or, (5/9)12-x

= (5/9)3

Or, 12-x

= 3

Or, x

= 12 – 36

= 9

(c) (4/11)× 4/11)8

= (4/11)15

Or, (4/11)x+8

= (4/11)15

Or, x + 8

= 15

Or, x

= 15 – 8

= 7

(d) (-3/4)x = (-3/4)÷ (-3/4)2

Or, (-3/4)= (-3/4)8-2

= (-3/4)6

Or, x = 6

Question no  – (9)

Solution :

No

Exponents and Powers exercise 5.3 solution :

Question no – (1)

Solution :

(a) 3.234 × 105

= 3234 × 105/103

= 3234 × 102

= 323400

(b) 0.84 × 107

=  84 × 107/100

= 84 × 107/102

= 84 × 105

= 8400000

(c) 1.6 × 10-5

= 16/10 × 10-5

= 16 × 10-6

= 16 × 0.000001

(d) 2.67 × 10-4

= 267/102 × 10-4

= 267 × 10-2

= 267 × 0.01

= 2.67

Question no – (2)

Solution :

(a) 44,51,00,00,000

= 4.451 × 1010

(b) 0.000675

=6.75 × 10-4

(c) 0. 00000083

= 8.3 × 10-7

(d) 12,30,00,00,00,000

= 1. 23 × 1012

Question no – (3)

Solution :

(a) 5 × 108, 9 × 106

= 500000000 > 90000000

(b) 2.4 × 107, 3.2 × 108

= 24000000 < 320000000

Question no – (4)

Solution :

= 300000

= 3 × 105 km/s

Question no – (5)

Solution :

CD = 1.6 × 10-3

= 0.0016

DVD = 7.4 × 10-4

= 0.00074

CD > DVD

Question no – (6)

Solution :

(a) heart beat about 1 min

= 60 time

= 1 hr = 60 × 60

= 3600 time

= 24 = 3600 × 24

= 86,400 time .

= 86400 × 365

= 31536000 time.

1 year blood pumps

= 31536000 × 8.3 × 10-2

= 31536 × 8.3 × 103 × 10-2

= 261748.8 × 10

(b) 20 year blood pumps

= 261748.8 × 20 × 10

Previous Chapter Solution :

Updated: May 27, 2023 — 6:05 am