Find the LCM and HCF of the following integers by applying the prime factorisation method.
(i) 12, 15 and 21
(ii) 17, 23 and 29
(iii) 8, 9 and 25
(i) 12 = 2×2×3 = 22×3
15 = 3×5
21 = 3×7
HCF = 3
LCM = 22×3×5×7 = 420
(ii) 17 = 1×17
23 = 1×23
29 = 1×29
HCF = 1
LCM = 17×23×29 = 11339
(iii) 8=2×2×2
9 = 3×3
25 = 5×5
HCF = 1
LCM = 2×2×2×3×3×5×5 = 1800