Question

lcm and hcf of 12,15,18 using prime factorisation method​

Answer 1

Answer:

HCF=3 and LCM =180

Step-by-step explanation:

Prime factor of 12 are 2, 2 and 3, since 12=2×2×3

prime factor of 15are 3 and 5 , since 15=3×5

prime factor of 18 are 2, 3 and 3, since 18=2×3×3

since the common prime factor is 3 only.

Therefore HCF of 12, 15 and 18 = 3

12=2×2×3

=2²×3¹

15=3×5

3¹×5¹

18=2×3×3

=2¹×3²

Therefore, required LCM = 2²×5¹×3²

=2×2×5×3×3

=180.

Hope it helps you.

Answer 2

H.C.F=3, L.C.M=60

Step-by-step explanation:

12=2×2×3=2^2×3

15=3×5

18=2×3×3

L.C.M= 2^2×3×5=60

H.C.F=3