Question

A pack of cards contains 4 kings 4 queens 4 jack and 4 ace what is the probability that at least one of them is an ace

Answer 1

as the total cards are 16 out of which 4 are ace so probability of at least one ace= 4/16=1/4

Answer 2

Number of cards of king = 4
Number of cards of queen = 4
Number of cards of jack = 4
Number of cards of ace = 4
∴ Total number of cards = 4 + 4 + 4 + 4 = 16
Probability of getting ace = 

Number of cards of ace
-------------------------------
  Total number of cards

$=\frac{4}{16} = \frac{1}{4}$

∴ The probability of getting ace is $\frac{1}{4}$. 

Hope this may help you. 

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