NCERT Solutions Class 6 Maths Chapter 3 Playing with Numbers Exercise 3.1

Class 6, Maths, Chapter 3, Exercise 3.1 Solutions

Q.1. Write all the factors of the following numbers:

(a) 24

(b) 15

(c) 21

(d) 27

(e) 12

(f) 20

(g) 18

(h) 23

(i) 36

Ans:

(a) 24

24 = 1 × 24

24 = 2 × 12

24 = 3 × 8

24 = 4 × 6

24 = 6 × 4

Hence, the factors of 24 are 1, 2, 3, 4, 6, 8, 12 and 24

 

(b) 15

15 = 1 × 15

15 = 3 × 5

15 = 5 × 3

Hence, the factors of 15 are 1, 3, 5 and 15

(c) 21

21 = 1 × 21

21 = 3 × 7

21 = 7 × 3

Hence, the factors of 21 are 1, 3, 7 and 21

(d) 27

27 = 1 × 27

27 = 3 × 9

27 = 9 × 3

Hence, the factors of 27 are 1, 3, 9 and 27

(e) 12

12 = 1 × 12

12 = 2 × 6

12 = 3 × 4

12 = 4 × 3

Hence, the factors of 12 are 1, 2, 3, 4, 6 and 12

(f) 20

20 = 1 × 20

20 = 2 × 10

20 = 4 × 5

20 = 5 × 4

Hence, the factors of 20 are 1, 2, 4, 5 10 and 20

 

(g) 18

18 = 1 × 18

18 = 2 × 9

18 = 3 × 6

18 = 6 × 3

Hence, the factors of 18 are 1, 2, 3, 6, 9 and 18

(h) 23

23 = 1 × 23

23 = 23 × 1

Hence, the factors of 23 are 1 and 23

(i) 36

36 = 1 × 36

36 = 2 × 18

36 = 3 × 12

36 = 4 × 9

36 = 6 × 6

Thus, the factors of 36 are 1, 2, 3, 4, 6, 9, 12, 18 and 36

Q.2. Write first five multiples of:

(a) 5

(b) 8

(c) 9

Ans:

(a) First five multiples of 5 are:

5 × 1 = 5

5 × 2 = 10

5 × 3 = 15

5 × 4 = 20

5 × 5 = 25

Hence, the first five multiples of 5 are 5, 10, 15, 20 and 25

 

(b) First five multiples of 8 are:

8 × 1 = 8

8 × 2 = 16

8 × 3 = 24

8 × 4 = 32

8 × 5 = 40

Hence, the first five multiples of 8 are 8, 16, 24, 32 and 40

(c) First five multiples of 9 are:

9 × 1 = 9

9 × 2 = 18

9 × 3 = 27

9 × 4 = 36

9 × 5 = 45

Hence, the first five multiples of 9 are 9, 18, 27, 36 and 45

Q.3. Match the items in column 1 with the items in column 2.

NCERT Solutions Class 6 Maths Ch. 3 Playing with Numbers Exe. 3.1 Q.3 a

Ans:  (i)(b), (ii) (d), (iii) (a), (iv) (f), (v) (e)

NCERT Solutions Class 6 Maths Ch. 3 Playing with Numbers Exe. 3.1 Q.3 b

Q.4. Find all the multiples of 9 upto 100.

Ans:

All the multiples of 9 up to 100 are:

9 × 1 = 9           

9 × 2 = 18

9 × 3 = 27

9 × 4 = 36

9 × 5 = 45

9 × 6 = 54

9 × 7 = 63

9 × 8 = 72

9 × 9 = 81

9 × 10 = 90

9 × 11 = 99

∴     All the multiples of 9 upto 100 are:

9, 18, 27, 36, 45, 54, 63, 72, 81, 90 and 99.

NCERT Solutions For Class 6 Maths, Chapter 3 Playing With Numbers (All Exercises)