cbse 6th Standard Mathematics Playing with Numbers Important Questions And Answers Study Material - QB365 Set A | QB365

6th Standard CBSE Syllabus & Materials

6th Standard CBSE

CBSE 6th Social Science The Value of Work - New Sample Question Papers Study Material - QB365 Set A

NEW

6th Standard CBSE

CBSE 6th Social Science Family and Community - New Sample Question Papers Study Material - QB365 Set A

NEW

6th Standard CBSE

CBSE 6th Social Science India's Cultural Roots - New Sample Question Papers Study Material - QB365 Set A

NEW

6th Standard CBSE

CBSE 6th Social Science India,That is Bharat - New Sample Question Papers Study Material - QB365 Set A

NEW

6th Standard CBSE

CBSE 6th Social Science Timeline and sources of history - New Sample Question Papers Study Material - QB365 Set A

NEW

6th Standard CBSE

CBSE 6th Social Science Oceans and Continents - New Sample Question Papers Study Material - QB365 Set A

cbse 6th Standard Mathematics Playing with Numbers Important Questions And Answers Study Material - QB365 Set A

Published on: 24/10/2025

Question Set A

cbse 6th Standard Mathematics Playing with Numbers Important Questions And Answers Study Material - QB365

Download CBSE Class 6th Standard CBSE Mathematics question papers, sample papers, important questions, and previous year solved papers in PDF format. Get free study materials, NCERT solutions, and exam preparation resources for Class 6th Standard CBSE Mathematics

Questions + Answers key

Take MCQ Mathematics Test

QB365 Student Learing Managemnet System

Std: 6th Standard CBSE - Mathematics

chapter: Playing with Numbers - Important Questions And Answers

Visit QB365-SLMS - https://www.qb365.in/slms/ Complete Questions and Answers

Questions:

Generic 2

40 x 2 = 80

Find the common factors of 7 and 16.

Express the following number as the sum of two odd primes 18

Find the prime factorisation of 90.

Find the prime factorisation of 630.

Are 97 and 47 co-prime?

Give prime factorisation of 60775.

Give the prime factorisation of 20570.

Write all the common factors between 12 and 64.

A number is divisible by 3, 4, 5 and 13. Is that number also divisible by 780?

10.

4096 is divisible by 64. Can we say it is divisible by 8 also?

11.

A number is divisible by 8. By what other numbers will that number be divisible?

12.

Is 47 and 56 co-prime numbers?

13.

Find the common factors of 42 and 70

14.

Find the common factors of 25 and 80

15.

A number is divisible by both 5 and 12. By which other number will that number be always divisible?

16.

Find first three common multiples of 12 and 18

17.

Find first three common multiples of 6 and 8

18.

Find the common factors of 5, 15 and 25

19.

Find the common factors of 56 and 120

20.

Find the common factors of 9, 15

21.

Which of the following pairs are co-prime?
(a) 8, 25
(b) 4, 10

22.

Find the common factors of 8 and 20.

23.

Is the number 17152652 divisible by both 4 and 11?

24.

Is 93455120 divisible by 11?

25.

Using divisibility tests, determine the following number are divisible by 4 and 8?
5500

26.

Express the following number as sum of two prime numbers. 49

27.

Express each of the following numbers as the sum of three odd primes 31

28.

Express each of the following numbers as the sum of three odd primes 21

29.

Express the following as the sum of two odd prime numbers 32

30.

Write all the factors of the following number 60

31.

Find all the multiples of 9 upto 100

32.

Write first five multiples of 8

33.

Write first five multiples of 5

34.

Write all the factors of the following number: 23

35.

Write all the factors of the following number: 18

36.

Write all the factors of the following number: 20

37.

Write all the factors of the following number: 21

38.

Write all the factors of the following number: 15

39.

Write all the factors of the following number: 24

40.

Find the factors of the first four multiples of 12.

Multiple Choice Question

15 x 1 = 15

41.

A number is divisible by 5 and 6. It may not be divisible by

(a)

(b)

(c)

(d)

42.

The HCF of 144 and 160 is

(a)

(b)

(c)

(d)

None of these

43.

The number of distinct prime factors of the smallest 5-digit number is

(a)

(b)

(c)

(d)

44.

Which of the following number is divisible by 8?

(a)

293

(b)

1205

(c)

1648

(d)

2063

45.

The number of distinct prime factors of the largest 4-digit number is

(a)

(b)

(c)

(d)

46.

The number of common prime factors of 75, 60, 105 is

(a)

(b)

(c)

(d)

47.

Which of the following is not co-prime?

(a)

8. 10

(b)

11, 12

(c)

1, 3

(d)

31, 33

48.

State which of the following is correct prime factorisation of the numbers.

(a)

7x13x31x37x46

(b)

7x13x31x37x47

49.

State which of the following is correct prime factorisation of numbers.

(a)

2x3x3x3x4=216

(b)

2x3x7x7x7x11=22638

50.

Which of the following is divisible by both 8 and 12?

(a)

1312

(b)

1626

(c)

1612

(d)

1926

(e)

None of the given number is divisible by 8 and 12

51.

Which of the following numbers is divisible by both 13 and 3?

(a)

1625

(b)

1296

(c)

121229

(d)

None of these

52.

Which of the following numbers is divisible by 11?

(a)

7249

(b)

250

(c)

1250

53.

Which of the following numbers is divisible by 3?

(a)

2592

(b)

5493

(c)

39583

54.

Using divisibility tests, determine which of the following numbers is divisible by 2?

(a)

315623

(b)

34678

(c)

789

(d)

2651

55.

A factor of 29161137 is

(a)

(b)

(c)

(d)

Visit QB365-SLMS - https://www.qb365.in/slms/

Answers Key:

Generic 2

40 x 2 = 80

Factors of 7 are: 1 and 7
Factors of 16 are: 1, 2, 4, 8 and 16
Hence, common factor of 7 and 16 is 1.

18 = 5 + 13 or 7 + 11

By factor tree method,

\(\therefore\) 90 = 2 x 3 x 3 x 5

By division method,

\(\therefore\) 630 = 2 x 3 x 3 x 5 x 7

Yes

5x5x11x13x17

2 x 5 x 11 x 11 x 17

Yes

10.

Yes, it is divisible by 8 also.

11.

1, 2, 4

12.

yes

13.

1, 2, 7, 14

14.

1,5

15.

The given number will be divisible by the product of 5 and 12. i.e. it is always divisible by 5 x 12 = 60.
Note If a number is divisible by two co-prime numbers, then it is divisible by their product also.

16.

Multiples of 12 = 12, 24, 36,48,60, 72, 84, 96, 108, 120, 132, ...
Multiples of 18 = 18, 36, 54, 72,90, 108, 126, 144, ...
Hence, first three common multiples are 36, 72 and 108.

17.

Multiples of 6 = 6, 12,18, 24, 30, 36, 42, 48, 54, 60, 66,72, ...
Multiples of 8 = 8, 16, 24, 32, 40, 48, 56, 64, 72, 80,88,96, ...
Hence, first three common multiples are 24, 48 and 72.

18.

Common factors of 5, 15 and 25 are 1 and 5.

19.

Factors of 56 and 120 are as follows:
56 = 1 x 56 ; 56 = 2 x 28 ; 56 = 4 x 14; 56 = 7 x 8 and 120 = 1 x 120 ; 120 = 2 x 60; 120 = 3 x 40; 120 = 4 x 30
120 = 5 x 24; 120 = 6 x 20; 120 = 8 x 15; 120 = 10 x 12
Now, all factors of 56 = 1, 2, 4, 7, 8, 14, 28, 56 and all factors of 120 = 1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 30, 40, 60, 120.
\(\therefore\)Common factors = 1, 2, 4, 8
Hence, common factors of 56 and 120 are 1, 2, 4 and 8.

20.

Factors of 9 and 15 are as follows:
9 = 1 x 9; 9 = 3 x 3 and 15 = 1 x 15; 15 = 3 x 5
Now, all factors of 9 = 1, 3, 9 and all factors of 15 = 1, 3, 5, 15
\(\therefore\)Common factors = 1,3
Hence, common factors of 9 and 15 are 1 and 3.

21.

(a) Factors of 8 = 1, 2, 4, 8
Factors of 25 = 1,5,25
\(\because\)8 and 25 have only 1 as common factor
\(\therefore\)8 and 25 are co-prime numbers.
(b) Factors of 4 = 1, 2, 4
Factors of 10 = 1,2,5,10
\(\because\)4 and 10 have 1,2 as common factors.
\(\therefore\)4 and 10 are not co-prime numbers.

22.

8=2x2x2x1
Factors of 8 are 1, 2, 4, 8.

12=2x2x3x1
Factors of 12 are 1, 2, 3, 4, 6, 12
Now, common factors of 8 and 12 are 1, 2, 4.

23.

Yes

24.

Yes

25.

5500 is divisible by 4.
5500 is not divisible by 8.

26.

47 + 2

27.

We have, 31 \(\Rightarrow\) 31= 3+5+23
where 3, 5 and 23 are odd prime numbers.

28.

We have, 21 \(\Rightarrow\) 21 = 3 + 5 + 13
where 3, 5 and 13 are odd prime numbers.

29.

Here, we have 32
32 = 29 +3

30.

1, 2, 3, 4, 5, 6,10,12,15,20,30,60

31.

Multiples of 9 upto 100 are as follows:
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
Hence, all the multiples of 9 upto 100 are 9,18,27,36,45, 54, 63, 72, 81, 90 and 99.

32.

Multiples of 8
8 x 1= 8; 8 x 2 = 16; 8 x 3 = 24; 8 x 4 = 32; 8 x 5 = 40
\(\therefore\)First five multiples of 8 are 8, 16, 24, 32 and 40.

33.

Multiples of 5,
5 x 1= 5; 5 x 2 = 10; 5 x 3 = 15; 5 x 4 = 20; 5 x 5 = 25
\(\therefore\)First five multiples of 5 are 5, 10, 15, 20 and 25.

34.

We have, 23
23 = 1x 23
\(\therefore\)Factors of 23 are 1 and 23.

35.

We have, 18
18 = 1 x 18; 18 = 2 x 9; 18 = 3 x 6
\(\therefore\)Factors of 18 are 1, 2, 3, 6, 9 and 18

36.

We have, 20
20 = 1 x 20; 20 = 2 x 10; 20 = 4 x 5
\(\therefore\)Factors of 20 are 1, 2, 4, 5, 10 and 20.

37.

We have, 21
21 = 1 x 21; 21 = 3 x 7
\(\therefore\)Factorsof 21 are 1, 3, 7 and 21.

38.

We have, 15
15 = 1 x 15; 15 = 3 x 5
\(\therefore\)Factors of 15 are 1, 3, 5 and 15.

39.

We have, 24
24 = 1x 24; 24 = 2 x 12; 24 = 3 x 8; 24 = 4 x 6
\(\therefore\) Factors of 24 are 1, 2, 3, 4, 6, 8, 12 and 24

40.

Factor is the exact divisor of that number. So, for finding factors, we use factorisation method.
Factors of 12 = 1, 2, 3, 4, 6 and 12.

Now, for finding multiples, we multiply 12 with natural numbers.
So, first four multiples of 12 are 12 x 1, 12 x 2, 12 x 3,12 x 4
i.e. 12, 24, 36 and 48.