Question

Find LCM of (i) 3, 4 (ii) 10, 11 (iii) 10, 30 (iv) 12, 24 (v) 3, 12 by prime factorization method.

Answer 1

i) Given numbers are 3, 4 

Factors of 3 = 1 x 3 

Factors of 4 = 2 x 2 

LCM of 3, 4 = 1 x 3 x 2 x 2 = 12 

ii) Given numbers are 10, 11 

Factors of 10 = 2 x 5 

Factors of 11 = 1 x 11 

LCM of 10, 11 = 2 x 5 x 11 = 110 

iii) Given numbers are 10, 30 

Factors of 10 = 2×5 

Factors of 30 = 2x3x5 

LCM of 10, 30 = 2 x 3 x 5 = 30 

iv) Given numbers are 12, 24 

Factors of 12 = 2x2x3 , 

Factors of 24 =. 2 x 2 x 2 x 3 

LCM of 12, 24 = 2 x 2 x 2 x 3 = 24

v) Given numbers are 3,12 

Factors of 3 = 1×3

Factors of 12 =2 x 2 x 3, 

LCM of 3, 12 = 3 x 2 x 2 = 12