It won't be possible to explain cards on doubt forum. kindly refer to the one of video on Youtube for this.

Acc to what was taught in class was...there are 52 total cards--> 26 Red and 26 Black, Red with 13 Hearts, 13 Diamonds, Black with 13 Club, 13 Spade, Face Cards--> 12, Jack, King, Queen in each Heart, Diamond, Cub, SpadeSo as per the question Even numbered back card is what was picked...so i thought that there are 26 total black cards, even would be 2-26(total-13 cards) & then it would be 13C2/52C2What I am missing such that in solution they have taken only 10 cards and not 13..?

Acc to what was taught in class was...there are 52 total cards--> 26 Red and 26 Black, Red with 13 Hearts, 13 Diamonds, Black with 13 Club, 13 Spade, Face Cards--> 12, Jack, King, Queen in each Heart, Diamond, Cub, SpadeSo as per the question Even numbered back card is what was picked...so i thought that there are 26 total black cards, even would be 2-26(total-13 cards) & then it would be 13C2/52C2What I am missing such that in solution they have taken only 10 cards and not 13..?

The total number of even-numbered black cards is 10 as there are the cards of 2, 4, 6, 8, and 10 belonging to both clubs and spades in a deck.

This should be 13..? as 2, 4,6,8,10,12,14,16,18,20,22,24,26 from 1-26...Can you also please explain the cards..? image.png 60.74 KB

This should be 13..? as 2, 4,6,8,10,12,14,16,18,20,22,24,26 from 1-26...Can you also please explain the cards..? image.png 60.74 KB