Suppose you draw two cards from a standard 52-card deck. Find the probability, when both cards are drawn without replacement, that the first card is a spade and the second card has a different suit.

18.75%
There are 4 suits in a standard deck and each hold 13 cards from ace to king. The probability of drawing a spade will be 25% because there is a 1/4 chance. To first draw a spade and then drawing a card that is not a spade is about 75% so if you multiply 0.25 and 0.75 together you get 0.1875 which equals 18.75%

1. 0.3 •4 is the same as 4 groups of 0.32. 7•0.8 is the same as 7 groups of 0.83. it increases by 0.5 every time, so 0.5x4 it increases by 0.9 every time, so 0.9x5. 0.9•12=10.86. 0.47•5=2.35i can finish the next ones in a separate post