RBSE Solutions for Class 6 Maths Chapter 3 Playing With Numbers InText Questions

Rajasthan Board RBSE Solutions for Class 6 Maths Chapter 3 Playing With Numbers InText Questions Textbook Exercise Questions and Answers.

RBSE Class 6 Maths Solutions Chapter 3 Playing With Numbers InText Questions

(Try These - Page 48)

Question 1.
Find the possible factors of 45, 30 and36.
Answer:
(i) All possible factors of 45 = 1, 3, 5, 9,15,45
(ii) All possible factors of 30
= 1, 2, 3, 5, 6,10,15, 30
(iii) All possible factors of 36 = 1, 2, 3, 4, 6,9,12,18, 36

(Try These - Page 52)

Question 1.
Observe that 2 × 3 + 1 = 7 is a prime number. Here, 1 has been added to a multiple of 2 to get a prime number. Can you find .some more number of this type?  
Answer:
Yes, we can have 2 × 1 + 1 = 3 which is a prime number.
2 × 2 + 1 = 5 which is a prime number.
2 × 5 + 1 = 11 which is a prime number.
2 × 6 + 1 = 13 which is a prime number.
2 × 8 + 1 = 17 which is a prime number.
2 × 9 + 1 = 19 which is a prime number.
2 × 11 + 1 = 23 which is a prime number.
2 × 13 + 1 = 27 which is a prime number And so on 

(Try These - Page 58)

Question 1.
Find the common factors of:
(a) 8, 20
(b) 9, 15
(a) Factors of 8 = 1, 2,4, 8,
Factors of 20 = 1, 2,4, 5,10, 20
Common factors of 8 and 20 are 1.

(b) Factors of 9 = 1, 3, 9
Factors of 15 = 1, 3, 5, 15
Common factors of 9 and 15 are 1 and 3.

Question 2.
Find the common factors of 7 and 16.
Answer:
Factors of 7 = 1 and 7
Factors of16 = 1, 2, 4, 8, 16
Common factors of 7 and 16 is 1.

Question 3.
Find the common factors of:
(a) 8,12, 20
(b) 9,15, 21
Answer:
(a) Factors of 8 = 1, 2,4, 8
Factors of 12 = 1, 2, 3, 4, 6, 12
Factors of 20 = 1, 2, 4, 5,10, 20
Common factors = 1, 2, 4.

(b) Factors of 9 = 1, 3, 9
Factors of 15 = 1, 3, 5, 15
Factors of 21 = 1, 3, 7
Common factors = 1, 3.

(Try These - Page 61)

Question 1.
Write the prime factorisations of 16, 28, 38.
Answer:
(i) Prime factorisation of 16 Or Factor tree of 16

∴ 16 = 2 × 2 × 2 × 2

(ii) Prime factorisation of 28 Or Factor tree of 38

∴ 28 = 2 × 2 × 7

(ii) Prime factorisation of 38 Or Factor tree of 38

(Try These - Page 63)

Question 1.
Find the HCF of the following:
(i) 24 and 36
(ii) 15, 25 and 30
(iii) 8 and 12
(iv) 12,16 and 28.
Answer:
(i) Factors of 24 are 1, 2, 3, 4, 6, 8,12 and 24.
Factors of 36 are 1,2,3,4,6,9,12,18 and 36.
Common factors are 1, 2, 3, 4, 6,12.
Highest common factor is 12.
∴ HCF of 24 and 36 = 12.

(ii) 15 = 1, 3, 5 and 15 25 = 1, 5 and 25
30 = 1, 2, 3, 5, 6,10,15 and 30
Highest common factor is 5.
∴ HCF of 15, 25, 30 = 5

(iii) 8 = 1, 2,4 and 8
12 = 1, 2, 3, 4, 6 and 12
Highest common factor is 4.
HCF of 8 and 12 = 4

(iv) 12 = 1, 2, 3, 4, 6 and 12 16 = 1, 2, 4, 8 and 16
28 = 1, 2,4, 7,14 and 28
Highest common factor is = 4.
∴ HCF of 12,16 and 28 = 4