Given: R=(1,3),(1,2)
To make R as Reflexive, the required elements are (1,1),(2,2),(3,3)and(4,4)
To make R as Symmetric, the required elements are (3,1)and(2,1)
To make R as Transitive, the required elements are (3,2)and(2,3)
So, 8 elements are required to make R an equivalence relation.
Hence, the total number of elements in R is 10.