April 4, 2009 - Probability & Cards

A standard deck of cards contains a total of 52 cards. Each of the four suits—Spade, Heart,
Diamond, and Club—contains 13 cards, 10 of them numbered from 2 to 10 and one each of an
A(ace), a J(jack), a Q(queen), and a K(king). The two jokers are excluded.

The probability of selecting a
card from the standard deck
and drawing a Queen of
Hearts is:
• 0.5
• 0.0192
• 1.0

Answer: 0.0192

The probability of drawing a
Queen from the deck is:
• 1
• 0
• 0.45
• 0.0769


Answer: 0.0769

What’s the probability of not
selecting a Queen from the
standard deck of cards?
• 0.9231
• 0.222
• 0.0769
• 0.126

Answer: 0.9231

Tip:
The key here is to know that
not selecting a Queen is the
complement of selecting a
Queen. In addition, from
Problem 2, we know that the
probability of selecting a
Queen is 0.0769.
Therefore, this problem can
be solved using the:
1. Probability of
selecting a Queen
2. Formula for finding
the probability of the
complement event,
P(E’) = 1 – P(E)