Probability of an event

So, there are 13 cards in the bag. That means every card has a probability of 1/13 of being chosen right. Of these thirteen cards, four of these cards are a multiple of three. 3,6,9 and 12. As such the probability of choosing any of these is (4*(1/13)) or 4/13.

I would like to point out that i hated stats in A-level maths and I haven't done it in close to two years so please check with your tutor or an answer sheet if this is correct or not.

Thank you Charlie101998, I might have more if you up to it.

Thank you Charlie101998, I might have more if you up to it.

The answer is correct. Thank you
I have 3 more to do.

A box is filled with 12 green cards, 2 brown cards, and 2 yellow cards. A card is chosen at random from the box. What is the probability that it is a green or a yellow card?

Write your answer as a fraction in simplest form.

I don't mind helping you out, i wanna go into teaching so it'd be good to sorta get feedback on how i explain stuff too.

Great, thank you. Here is the next question

A box is filled with 12 green cards, 2 brown cards, and 2 yellow cards. A card is chosen at random from the box. What is the probability that it is a green or a yellow card?

Write your answer as a fraction in simplest form.