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paul.9727593863
Nov 8, 2010, 08:43 AM
Suppose you roll a single die.
a.What is the probability that the number on the face is a 3 or a 6?
b.What is the probability that the number on the face is not a 2?
c.What is the probability that the number on the face is a 2 or a 4 or a 6?

Unknown008
Nov 8, 2010, 10:04 AM
The probability of an event A is given by the number of outcomes of A divided by the total number of outcomes.

If you want to find the probability of getting a head from tossing a fair coin, there is 1 head and two possibilities, head and tail. Probability of getting a head is therefore 1/2.

If you want to find the probability of getting a heart from drawing a card from a standard deck of cards, there is 13 hearts and 52 total cards. Probability of getting a heart is therefore 13/52 = 1/4

Now, the probability of getting something AND something else means you multiply the probabilities.

e.g.. Getting a head AND a heart = 1/2 x 13/52 = 1/8

Probability of getting something OR some other thing means you add the probabilities.

e.g.. Getting a head OR a heart = 1/2 + 13/52 = 3/4.


Now, try this with your problem and post what you get! :)