. Find the LCM and HCF of the following integers by applying the prime factorisation method.

⦁    12, 15 and 21
Solution:
12 = 2×2×3 = 22×3
15 = 3×5
21 = 3×7
HCF = 3
LCM = 22×3×5×7 = 420

⦁    17, 23 and 29
Solution:
17 = 1×17
23 = 1×23
29 = 1×29
HCF = 1
LCM = 17×23×29 = 11339


⦁     8, 9 and 25
Solution:
8=2×2×2
9 = 3×3
25 = 5×5
HCF = 1
LCM = 2×2×2×3×3×5×5 = 1800