Question

Find HCF of 54, 72 and 90 by prime factorisation method

Answer 1

54 = 2×3×3×3
72 = 2×2×3×3×2
90 = 2×3×3×5
HCF = 2×3×3 = 18

Answer 2

Given:

Number are 54, 72 and 90.

To Find:

Find HCF of 54, 72 and 90 by prime factorisation method.

Solution:

Prime factorization of given number are:

54 = 2 ×3 ×3 ×3

72 = 2 ×2 ×2 ×3 ×3

90 = 2 ×3 ×3 ×5

We know that highest common factor is multiplication of all common factor of prime factorization of all number, So:

H.C.F = 2 ×3 ×3 =18

So HCF of 54, 72 and 90 by prime factorisation method is 18.