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Asifpirlo
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WINK, Inc. follows a certain procedure that requires two tas 21 Aug 2013, 18:50
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96% (00:55) correct 4% (01:32) wrong based on 112 sessions

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WINK, Inc. follows a certain procedure that requires two tasks to be finished independently in order for a job to be done. On any given day, there is a 7/8 probability that task 1 will be completed on time, and a 3/5 probability that task 2 will be completed on time. On a certain day, what is the probability that task 1 will be completed on time, but task 2 will not?

A. 1/20
B. 3/40
C. 13/40
D. 7/20
E. 13/22
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D
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madhurs254
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WINK, Inc. follows a certain procedure that requires two tas 21 Aug 2013, 19:03
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Asifpirlo
WINK, Inc. follows a certain procedure that requires two tasks to be finished independently in order for a job to be done. On any given day, there is a 7/8 probability that task 1 will be completed on time, and a 3/5 probability that task 2 will be completed on time. On a certain day, what is the probability that task 1 will be completed on time, but task 2 will not?
A. 1/20
B. 3/40
C. 13/40
D. 7/20
E. 13/22
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7/20...
Explanation: 7/8 * 2/5
where 2/5 is the probability of task 2 not getting completed on time...
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Bunuel
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WINK, Inc. follows a certain procedure that requires two tas 22 Aug 2013, 03:57
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Asifpirlo
WINK, Inc. follows a certain procedure that requires two tasks to be finished independently in order for a job to be done. On any given day, there is a 7/8 probability that task 1 will be completed on time, and a 3/5 probability that task 2 will be completed on time. On a certain day, what is the probability that task 1 will be completed on time, but task 2 will not?

A. 1/20
B. 3/40
C. 13/40
D. 7/20
E. 13/22
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P(1 and not 2)=7/8*(1-3/5)=14/40=7/20.

Answer: D.
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vivekdixit07
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WINK, Inc. follows a certain procedure that requires two tas 20 Jan 2021, 19:48
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Bunuel
Asifpirlo
WINK, Inc. follows a certain procedure that requires two tasks to be finished independently in order for a job to be done. On any given day, there is a 7/8 probability that task 1 will be completed on time, and a 3/5 probability that task 2 will be completed on time. On a certain day, what is the probability that task 1 will be completed on time, but task 2 will not?

A. 1/20
B. 3/40
C. 13/40
D. 7/20
E. 13/22

P(1 and not 2)=7/8*(1-3/5)=14/40=7/20.

Answer: D.
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Why do we multiple the probabilities of A & B and not add? If tasks are independent then should we not add the probabilities of A & 'Not B"?
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