Let R={(2,3),(3,4)}  be a relation defined on the set of natural numbers. The minimum number of ordered pairs required to be added in R so that the enlarged relation becomes an equivalence relation is

To make it reflexive , we need to add (2, 2) (3, 3) , (4, 4)To make it symmetric , we need to add (3, 2) (4, 3)To make it transitive , we need to add (2, 4) (4, 2) so that the relationR={(2,2)(3,3)(4,4)(2,3)(3,2)(3,4)(4,3)(2,4)(4,2)}Hence we need to add 7 more