Q4 of 20 Page 1

Let * be a binary operation on N given by a*b = LCM(a, b) for all a, b ∊ N. Find 5*7. [CBSE 2012]

Given: a*b = LCM(a, b)


5*7 = LCM(5, 7)


= 5 × 7


= 35


Hence, 5*7 = 35


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