consider the experiment of selecting a card from

an ordinary deck of 52 playing cards and determine the probability
of the stated event.

A red card or a card showing a 5 is drawn.

There are 26 red cards and 2 extra fives. Would my answer be 28/52?

3 answers

yes
Does this mean that we do not count the two red fives as they would already be counted in the reds.
I would assume that you determined the two probabilities separately.

Red cards = 26/52

5 = 4/52

Either-or probability determined by adding the individual probabilities.