Question

Q19 : Find the HCF and the LCM of the following by prime factorization. a) 360 , 756
b) 2x
4
y
3
z , 32x
3
y
4
p

Answer 1

Step-by-step explanation:

Express 18 and 45 as product of primes.

18=2×3×3×=2×3

2

45=3×3×5=3

2

×5

∴ HCF of 18 and 45=3×3=9

LCM of 18 and 45=3×3×2×5=90

Recall : HCF of any 2 positive integers is the product of the smallest power of each common prime factor of the numbers.

LCM of any 2 positive integers is the product of the greatest power of each factor of the numbers.