Question 1110063
A jar contains four marbles labeled "1", "2", "3", and "4". Two marbles are drawn without replacement. Determine the probability that
a. The sum of the numbers on the drawn marbles = 5
ways to get "5":: 1/4 ; 2/3
# of number pairs:: 4C2 = 6
Ans:: 2/6 = 1/3
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b. The sum of the numbers on the drawn marbles is an odd numbers
ways to get odd sum:: 1/2 ; 1/4; 2/3 ; 3/4
Ans:: 4/6 = 2/3
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c. The sum of the number on the drawn marble = 9
way to get "sum of 9":: none 
Ans: 0
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d. one of the marbles drawn is the "3" marble
ways to get "3":: 1/3 ; 2/3 ; 4/3
Ans: 3/6 = 1/2
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Cheers,
Stan H.
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