**Playing With Numbers Class 6 Ex. 3.1**

**Ncert Class 6 Math Free Solution.**

**Exercise 3.1**

**Question 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**

**Solution 1:-**

(a) Factors of 24 are:

24 = 1 x 24;

24 = 2 x 12;

24 = 3 x 8;

24 = 4 x 6

So, all the factors of 24 are :- 1, 2, 3, 4, 6, 8, 12 and 24.

(b) Factors of 15 are:

15 = 1 x 15;

15 = 3 x 5

So, all the factors of 15 are :- 1, 3, 5 and 15.

(c) Factors of 21 are:

21 = 1 x 21;

21 = 3 x 7

So, all the factors of 21 are :- 1, 3, 7 and 21.

(d) Factors of 27 are:

27 = 1 x 27;

27 = 3 x 9.

So, all the factors of 27 are :- 1, 3, 9 and 27.

(e) Factors of 12 are:

12 = 1 x 12;

12 = 2 x 6;

12 = 3 x 4

So, all the factors of 12 are :- 1, 2, 3, 4, 6 and 12.

(f) Factors of 20 are:

20 = 1 x 20;

20 = 2 x 10;

20 = 4 x 5

So, all the factors of 20 are :- 1, 2, 4, 5, 10 and 20.

(g) Factors of 18 are:

18 = 1 x 18;

18 = 2 x 9;

18 = 3 x 6;

So, all the factors of 18 are :- 1, 2, 3, 6, 9 and 18.

(h) Factors of 23 are:

23 = 1 x 23;

So, all the factors of prime number 23 are :- 1 and 23.

(i) Factors of 36 are:

36 = 1 x 36;

36 = 2 x 18;

36 = 3 x 12;

36 = 4 x 9;

36 = 6 x 6;

So, all the factors of 36 are :- 1, 2, 3, 4, 6, 9, 12, 18 and 36.

**Question 2 :- Write first five multiples of :-**

**(a) 5 (b) 8 (c) 9**

**Solution:**

(a) First five multiples of 5 are:

5 x 1 = 5;

5 x 2 = 10;

5 x 3 = 15;

5 x 4 = 20;

5 x 5 = 25;

So, the required multiples of 5 are :- 5, 10, 15, 20 and 25.

(b) First five multiples of 8 are:

8 x 1 = 8;

8 x 2 = 16;

8 x 3 = 24;

8×4 = 32;

8 x 5 = 40;

So, the required multiples of 8 are :- 8, 16, 24, 32 and 40.

(c) First five multiples of 9 are:

9 x 1 = 9;

9 x 2 = 18;

9 x 3 = 27;

9 x 4 = 36;

9 x 5 = 45;

So, the required multiples of 9 are :- 9,18, 27, 36 and 45.

**Question 3 :- Match the items in column I with the items in column II.**

** Column 1 Column 2**

(i) 35 (a) Multiple of 8

(ii) 15 (b) Multiple of 7

(iii) 16 (c) Multiple of 70

(iv) 20 (d) Factor of 30

(v) 25 (e) Factor of 50

(f) Factor of 20

**Solution 3:-**

(i) → (b) {because, 7 x 5 = 35}

(ii) → (d) {because, 15 x 2 = 30}

(iii) → (a) {because, 8 x 2 = 16}

(iv) → (f) {because, 20 x 1 = 20}

(v) → (e) {because, 25 x 2 = 50}

**Question 4 :- Find all the multiples of 9 upto 100.**

**Solution 4:-**

9 x 1 = 9;

9 x 2 = 18;

9 x 3 = 27;

9 x 4 = 36;

9 x 5 = 45;

9 x 6 = 54;

9 x 7 = 63;

9 x 8 = 72;

9 x 9 = 81;

9 x 10 = 90;

9 x 11 = 99;

So, all the multiples of 9 upto 100 are :-

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

**Playing With Numbers Class 6 Exercise. 3.1 for Free**