Question 1 - Page 122 - Uses of Prime Factorisation - Chapter 5 Class 6 - Prime Time (Ganita Prakash)

Transcript

Question 1 - Page 122 - (a) Are the following pairs of numbers co-prime? Guess first and then use prime factorisation to verify your answer. a. 30 and 45 Doing prime factorization of each Since 30 & 45 have 3 & 5 as common prime factors ∴ They are not coprime ∴ 45 = 3 × 3 × 5 ∴ 30 = 2 × 3 × 5 Question 1 - Page 122 - (b) Are the following pairs of numbers co-prime? Guess first and then use prime factorisation to verify your answer. b. 57 and 85 Doing prime factorization of each Since 57 & 85 have no common prime factors ∴ They are coprime Question 1 - Page 122 - (c) Are the following pairs of numbers co-prime? Guess first and then use prime factorisation to verify your answer. c. 121 and 1331 Doing prime factorization of each Since 121 & 1331 have 11 & 11 as common prime factors ∴ They are not coprime Question 1 - Page 122 - (d) Are the following pairs of numbers co-prime? Guess first and then use prime factorisation to verify your answer. d. 343 and 216Doing prime factorization of each Since 343 & 216 have no common prime factors ∴ They are coprime