jcaguirre91
In a class, every student is either American or European. Every student is wearing a blazer or a sweater. If a student is selected randomly, is the probability of the student being a European wearing a sweater greater than that of his/her being an American wearing a blazer?
(1) The probability that a randomly selected student is either American or wearing a blazer is 5/6.
(2) The probability that a randomly selected student is either a European or wearing a sweater is 3/5.
We can also use a 2 * 2 matrix to plot the information.
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AMR ⇒ Students who are Americans
EUR ⇒ Students who are Europeans
BLZ ⇒ Students who wear blazers
SWT ⇒ Students who wear sweaters
We need to find if \(x \geq y\)
Statement 1(1) The probability that a randomly selected student is either American or wearing a blazer is 5/6.
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We have been presented with the combined probability of a student who is a part of the blocks indicated by a red cross.
The sum of the probability of all four boxes equals 1
Probability of a European wearing a sweater = \(1-\frac{5}{6} = \frac{1}{6}\)
However, we do not have any information on the probability of an American wearing a blazer. Hence, this statement alone is not sufficient.
Statement 2Attachment:
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(2) The probability that a randomly selected student is either a European or wearing a sweater is 3/5
We have been presented with the combined probability of a student who is a part of the blocks indicated by a green cross.
The sum of the probability of all four boxes equals 1
Probability of an American wearing a blazer = \(1-\frac{3}{5} = \frac{2}{5}\)
However, we do not have any information on the probability of a European wearing a sweater. Hence, this statement alone is not sufficient.
CombinedAttachment:
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As we have both probabilities, we can compare the values and obtain a definite answer to the question. The statements combined are sufficient.
Option C