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Machines A and B operate independently of each other.
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Updated on: 14 Oct 2019, 08:59
Updated on: 14 Oct 2019, 08:59
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Question Stats:
65% (00:55) correct
34% (00:51) wrong based on 86 sessions
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Machines A and B operate independently of each other.
The probability that machine A operates properly is 0.4
The probability that machine B operates properly is 0.3
A)The quantity in Column A is greater.
B)The quantity in Column B is greater.
C)The two quantities are equal.
D)The relationship cannot be determined from the information given.
Due to the rights issue, I changed the question numbers and didn't mention the resource
The probability that machine A operates properly is 0.4
The probability that machine B operates properly is 0.3
Quantity A |
Quantity B |
The probability that exactly one machine operates properly |
0.54 |
A)The quantity in Column A is greater.
B)The quantity in Column B is greater.
C)The two quantities are equal.
D)The relationship cannot be determined from the information given.
Due to the rights issue, I changed the question numbers and didn't mention the resource
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Re: Machines A and B operate independently of each other.
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14 Oct 2019, 13:33
14 Oct 2019, 13:33
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Asmakan wrote:
Machines A and B operate independently of each other.
The probability that machine A operates properly is 0.4
The probability that machine B operates properly is 0.3
A)The quantity in Column A is greater.
B)The quantity in Column B is greater.
C)The two quantities are equal.
D)The relationship cannot be determined from the information given.
Due to the rights issue, I changed the question numbers and didn't mention the resource
The probability that machine A operates properly is 0.4
The probability that machine B operates properly is 0.3
Quantity A |
Quantity B |
The probability that exactly one machine operates properly |
0.54 |
A)The quantity in Column A is greater.
B)The quantity in Column B is greater.
C)The two quantities are equal.
D)The relationship cannot be determined from the information given.
Due to the rights issue, I changed the question numbers and didn't mention the resource
If events A and B are independent, then P(A and B) = P(A) x P(B)
If P(machine A operates properly) = 0.4, then P(machine A does NOT operate properly) = 0.6
If P(machine B operates properly) = 0.3, then P(machine B does NOT operate properly) = 0.7
Want to determine: P(exactly one machine operates properly)
There are two ways in which exactly one machine operates properly:
1) machine A operates properly AND machine B does NOT operate properly
OR
2) machine B operates properly AND machine A does NOT operate properly
Let's calculate each probability
1) machine A operates properly AND machine B does NOT operate properly
P(machine A operates properly AND machine B does NOT operate properly) = P(machine A operates properly) x P(machine B does NOT operate properly)
= 0.4 x 0.7
= 0.28
2) machine B operates properly AND machine A does NOT operate properly
P(machine B operates properly AND machine A does NOT operate properly) = P(machine B operates properly) x P(machine A does NOT operate properly)
= 0.3 x 0.6
= 0.18
So, P(exactly one machine operates properly) = 0.28 + 0.18
= 0.46
We get:
QUANTITY A: 0.46
QUANTITY B: 0.54
Answer: B
Cheers,
Brent
General Discussion
Re: Machines A and B operate independently of each other.
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14 Oct 2019, 00:26
14 Oct 2019, 00:26
1
My question : when solving
I solve it as Probability of machine A or B works probably. But the solution didn't work out.
I solve it as Probability of machine A or B works probably. But the solution didn't work out.
