The face cards are removed from a full pack. Out of the remaining 40 cards, 4 are drawn at random. What is the probability that they belong to different suits?
given: pack of 52 cards from which face cards are removed
formula: 
four cards are drawn from the remaining 40 cards, so we have to find the probability that all of them belong to different suit
total possible outcomes of drawing four cards are 40C4
therefore n(S)= 40C4
let E be the event that 4 cards belong to different suit
n(E)= 10C110C110C110C1=10000
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