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Let A={2,3,4,5,…,30}A = \{2, 3, 4, 5, \dots, 30\} and '≍\asymp' be an equivalence relation on A×AA \times A, defined by (a,b)≍(c,d)(a, b) \asymp (c, d), if and only if ad=bcad = bc. Then the number of ordered pairs which satisfy this equivalence relation with ordered pair (4,3)(4, 3) is equal to
Sets, Relations and Functions - Medium - Question