From a well shuffled pack of 52 playing cards, four are drawn at random. The probability that all are spades, but one is a king is:
Total No. Of cards =52
Total cards of spade =13
Probability=Conditional casetotal case
So,
Total no. Of conditional case of drawing 4 cards of spade but one is king = no. of case of selecting all four cards of spade suit
= 12C3×1
Total no. of case = 52C4
Probability of being one card as king out of four =12C352C4