(i) 8 = 2 × 2 × 2 = 23
9 = 3 × 3 = 32
25 = 5 × 5 = 52
HCF = product of smallest power of each common prime factor in the numbers = 1
LCM = product of greatest power of each prime factor involved in the numbers
= 23 × 32 × 52 = 1800
(ii) 12 = 2 × 2 × 3 = 22 × 3
15 = 3 × 5
21 = 3 × 7
HCF = product of smallest power of each common prime factor in the numbers = 3
LCM = product of greatest power of each prime factor involved in the numbers
= 22 × 3 × 5 × 7 = 420
(iii) 17 = 17
23 = 23
29 = 29
HCF = product of smallest power of each common prime factor in the numbers = 1
LCM = product of greatest power of each prime factor involved in the numbers
= 17 × 23 × 29 = 11339
(iv) 24 = 2 × 2 × 2 × 3 = 23 × 3
36 = 2 × 2 × 3 × 3 = 22 × 32
40 = 2 × 2 × 2 × 5 = 23 × 5
HCF = product of smallest power of each common prime factor in the numbers
= 22 = 4
LCM = product of greatest power of each prime factor involved in the numbers
= 23 × 32 × 5 = 360
(v) 30 = 2 × 3 × 5
72 = 2 × 2 × 2 × 3 × 3 = 23 × 32
432 = 2 × 2 × 2 × 2 × 3 × 3 × 3 = 24 × 33
HCF = product of smallest power of each common prime factor in the numbers
= 2 × 3 = 6
LCM = product of greatest power of each prime factor involved in the numbers
= 24 × 33 × 5 = 2160
(vi) 21 = 3 × 7
28 = 2 × 2 × 7 = 22 × 7
36 = 2 × 2 × 3 × 3 = 22 × 32
45 = 5 × 3 × 3 = 5 × 32
HCF = product of smallest power of each common prime factor in the numbers = 1
LCM = product of greatest power of each prime factor involved in the numbers
= 22 × 32 × 5 × 7 = 1260