Find the common factors of :
(a)  20 and 28            
(b) 15 and 25        
(c)   35 and 50        
(d)  56 and 120

Explanation

(a) Given numbers are : 20 and 28

Factors of 20 are 1, 2, 4, 5, 10, 20

Factors of 28 are 1, 2, 4, 7, 28

Hence, the common factors are 1, 2 and 4.


(b) Given numbers are: 15 and 25

Factors of 15 are 1, 3, 5, 15

Factors of 25 are 1, 5, 25

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