Question

4 cards are drawn from a deck of 52 well shuffled cards. What is the probability that all the 4 cards are not of different suits.​

Answer 1

So are you drawing a card noting what card it is, and then returning it to the deck and drawing a second card, noting it returning it and repeating for a third and fourth card? In this case (52/52) x (51/52) x (50/52) x (49/52) = approximately 88.86%

Otherwise I am assuming you are not returning cards to the deck after they have been drawn. So if cards are not returned, each card is sure to be different. 100%

Do you mean each card is from a different suit?

(52/52) x (39/51) x (26/50) x (13/49) = approximately 10.55%

Do you mean each has a different value 2–10, J, Q, K, or A?

(52/52) x (48/51) x (44/50) x (40/49) = approximately 67.61%

Hope it helps