## NCERT Exercise 3.1 Solution class 6 math

**Question (1)** Write all the factors of the following numbers:

(a) Find all the factors of 24

**Solution**

24 ÷ 1 = 24

Thus, 24 = 24 × 1

24 ÷ 2 = 12

Thus, 24 = 12 × 2

24 ÷ 3 = 8

Thus, 24 = 8 × 3

24 ÷ 4 = 6

Thus, 24 = 6 × 4

Thus, factors of 24 = 1, 2, 3, 4, 6, 8, 12, and 24 **Answer**

**(b)** Find all the factors of 15

**Solution**

15 ÷ 1 = 15

Thus, 15 = 15 × 1

15 ÷ 3 = 5

Thus 15 = 3 × 5

Thus, factors of 15 = 1, 3, 5, and 15 **Answer**

**(c)** Find all the factors of 21

**Solution**

21 ÷ 1 = 21

Thus, 21 = 21 × 1

21 ÷ 3 = 7

Thus, 21 = 7 × 3

Thus, factors of 21 = 1, 3, 7, and 21 **Answer**

**(d)** Find all the factors of 27

**Solution**

27 ÷ 1 = 27

Thus, 27 = 1 × 27

27 ÷ 3 = 9

Thus, 27 = 3 × 9

Thus, factors of 27 = 1, 3, 9, and 27 **Answer**

**(e)** Find all the factors of 12

12 ÷ 1 = 12

Thus, 12 = 1 × 12

12 ÷ 2 = 6

Thus, 12 = 2 × 6

12 ÷ 3 = 4

Thus, 12 = 3 × 4

Thus, factors of 12 = 1, 2, 3, 4, 6, and 12 **Answer**

**(f)** Find all the factors of 20

**Solution**

20 ÷ 1 = 20

Thus, 20 = 1 × 20

20 ÷ 2 = 10

Thus, 20 = 2 × 10

20 ÷ 4 = 5

Thus, 20 = 4 × 5

Thus, factors of 20 = 1, 2, 4, 5, 10, and 20 **Answer**

**(g)** Find all the factors of18

**Solution**

18 ÷ 1 = 18

Thus, 18 = 1 × 18

18 ÷ 2 = 9

Thus, 18 = 2 × 9

18 ÷ 3 = 6

Thus, 18 = 3 × 6

Thus, factors of 18 = 1, 2, 3, 6, 9, and 18 **Answer**

**(h)** Find all the factors of 23

**Solution**

23 ÷ 1 = 23

Thus, factors of 23 = 1, and 23 **Answer**

**(i)** Find all the factors of 36

**Solution**

36 ÷ 1 = 36

Thus, 36 = 1 × 36

36 ÷ 2 = 18

Thus, 36 = 2 × 18

36 ÷ 3 = 12

Thus, 36 = 3 × 12

36 ÷ 4 = 9

Thus, 36 = 4 × 9

36 ÷ 6 = 6

Thus, 36 = 6 × 6

Thus, factors of 36 = 1, 2, 3, 4, 6, 9, 12, 18, and 36 **Answer**

**Question (2)** Write first five multiples of:

(a) Find five multiples of 5

**Solution**

First multiple of 5

= 5 × 1 = 5

Second multiple of 5

= 5 × 2 = 10

Third multiple of 5

= 5 × 3 = 15

Fourth multiple of 5

= 5 × 4 = 20

And, the fifth multiple of 5

= 5 × 5 = 25

Thus, 5 multiples of 5 = 5, 10, 15, 20, and 25 **Answer**

(b) Find five multiples of 8

**Solution**

First multiple of 8

= 8 × 1 = 8

Second multiple of 8

= 8 × 2 = 16

Third multiple of 8

= 8 × 3 = 24

Fourth multiple of 8

= 8 × 4 = 32

And, the fifth multiple of 8

= 8 × 5 = 40

Thus, 5 multiples of 8 = 8, 16, 24, 32, and 40 **Answer**

(c) Find five multiples of 9

**Solution**

First multiple of 9

= 9 × 1 = 9

Second multiple of 9

= 9 × 2 = 18

Third multiple of 9

= 9 × 3 = 27

Fourth multiple of 9

= 9 × 4 = 36

And, the fifth multiple of 9

= 9 × 5 = 45

Thus, 5 multiples of 9 = 9, 18, 27, 36, and 45 **Answer**

**Question (3)** Match the items in column I with the items in column 2

Column I | Column II |

(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 |

**Answer**

Column I | Column II |

(i) 35 | (b) Multiple of 7 |

(ii) 15 | (d) Factor of 30 |

(iii) 16 | (a) Multiple of 8 |

(iv) 20 | (f) Factor of 20 |

(v) 25 | (e) Factor of 50 |

(c) Multiple of 70 |

**Question (4)** Find all the multiples of 9 upto 100.

**Solution**

(1) 9 × 1 = 9

(2) 9 × 2 = 18

(3) 9 × 3 = 27

(4) 9 × 4 = 36

(5) 9 × 5 = 45

(6) 9 × 6 = 54

(7) 9 × 7 = 63

(8) 9 × 8 = 72

(9) 9 × 9 = 81

(10) 9 × 10 = 90

(11) 9 × 11 = 99

Thus, there are total eleven multiples of 9 upto 100 which are equal to 9, 18, 27, 36, 45, 54, 63, 72, 81, 90, 99 **Answer**