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The probability that student X will take history in the next
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19 Oct 2019, 05:51
19 Oct 2019, 05:51
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Question Stats:
57% (02:27) correct
42% (01:20) wrong based on 14 sessions
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The probability that student X will take history in the next semester is 0.75, the probability that at least one of students X and Y will take history in the next semester is 0.94, and whether or not one of students X and Y will take history in the next semester is independent of whether or not the other of these students will take history in the next semester. What is the probability that student Y will take history in the next semester?
may someone solves for me this question step by step ?
#s are changed due to rights
Show: :: OA
0.76
may someone solves for me this question step by step ?
#s are changed due to rights
Re: The probability that student X will take history in the next
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19 Oct 2019, 06:31
19 Oct 2019, 06:31
Expert Reply
This is a question stright from the ETS GRE test ??
From where ??
Thanks for the clarification
From where ??
Thanks for the clarification
Re: The probability that student X will take history in the next
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26 Oct 2019, 16:59
26 Oct 2019, 16:59
2
The formula for independent events is -
1)P(XUY)=P(X)+P(Y)-P(XnY)
2)P(XnY)=P(X) x P(Y)
Here P(XUY) is the probability that at least one event occurs and P(XnY) means that both events will occur.
So, the values given are-
P(XUY)=0.94
P(X)=0.75
0.94=.75+P(Y)-P(XnY)
0.94-0.75=P(Y)-0.75xP(Y)
0.25xP(Y)=0.19
4x0.25xP(Y)=4x0.19
P(Y)=0.56
1)P(XUY)=P(X)+P(Y)-P(XnY)
2)P(XnY)=P(X) x P(Y)
Here P(XUY) is the probability that at least one event occurs and P(XnY) means that both events will occur.
So, the values given are-
P(XUY)=0.94
P(X)=0.75
0.94=.75+P(Y)-P(XnY)
0.94-0.75=P(Y)-0.75xP(Y)
0.25xP(Y)=0.19
4x0.25xP(Y)=4x0.19
P(Y)=0.56
