Six cards numbered from 1 to 6 are placed in an empty bowl. First one card is drawn and then put back. Then second card is drawn. If cards are drawn at random and is sum of numbers on cards is 8, what is the Probability that one of the two cards drawn is numbered 5?
1) 1/6
2) 1/5
3) 1/3
4) 2/5
5) 2/3
Probability: 5 numbered card
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Total Outcomes (sum of card=8) = {2,6} {3,5} {4,4} {5,3} {6,2} = 5avanti@gmat wrote:Six cards numbered from 1 to 6 are placed in an empty bowl. First one card is drawn and then put back. Then second card is drawn. If cards are drawn at random and is sum of numbers on cards is 8, what is the Probability that one of the two cards drawn is numbered 5?
1) 1/6
2) 1/5
3) 1/3
4) 2/5
5) 2/3
Favorable Total Outcomes = {3,5} {5,3} = 2
Probability = Favorable Outcomes/Total Outcomes
Probability = 2/5
Answer: Option D
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There are 36 possible EQUALLY LIKELY outcomes in this scenario: (1,1), (1,2), (1,3)... etc.avanti@gmat wrote:Six cards numbered from 1 to 6 are placed in an empty bowl. First one card is drawn and then put back. Then second card is drawn. If cards are drawn at random and is sum of numbers on cards is 8, what is the Probability that one of the two cards drawn is numbered 5?
1) 1/6
2) 1/5
3) 1/3
4) 2/5
5) 2/3
Let's examine those outcomes where the sum is 8: (2,6), (3,5), (4,4), (5,3) and (6,2)
We're told that one of these five outcomes occurred, AND one of the numbers is a 5
Of those 5 outcomes, 2 meet the condition that one of the numbers is a 5, so the probability = [spoiler]2/5[/spoiler]
Cheers,
Brent