Clearly ,   n(S) =   `52_(C _2) =  ((52 xx 51))/(2)` = 1326.

Let  `E_1` = event of getting both red cards .

        `E_2` = event of getting both kings.

Then ,  `E_ 1 nn E_2` = event of getting  2 kings of red cards.

`:.`        `n(E_1) = 26_(C_2) = ((26 xx 25))/((2 xx 1))` = 325.

            ` n(E_2)  = 4_(C_ 2) =  ((4 xx 3))/((2 xx 1))` = 6.

            `n(E_1 nn E_2) = 2_(C_2)` = 1.

`:.`       `P(E_1) = (n(E_1))/(n(S)) = 325/1326`

            `P(E_2) = (n(E _ 2))/(n(S)) = 6/1326`

         `P (E_1 nn E_2) = 1/1326`

`:.`     P(both red or both kings) = `P (E_1 uu E_2)`

                                                   =`P(E_1) + P(E_2) - P(E_1 nn E_2)`

                                                   =  `( 325/1326 + 6/1326 - 1/1326)`

                                                    = ` 330/1326 = 55/221`