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rexxii
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- Probability - z value - stats issue
Hi,
I'm working on a question now where I need to calculate the z value. which I have been able to but I'm calculating a value off the normal distribution that is on the left-hand side of the normal distribution curve and it needs to on the right side. As the value I'm looking into is higher than the mean!
I cannot figure out how I would turn this around. its only one independent event there's no replacement or other variables.
the question is:
A cable manufacturer tests the cables it produces to find the breaking load. Over many years this has been assumed to be normally distributed with a mean of 6000 Newtons and standard deviation of 155 Newtons. Calculate the probability that a single cable chosen at random, will have a breaking load greater than 6200 N. Z = 6200 -6000 /155 = 1.29
Then I've written a probability statement (P z>1.290) = P z>1.290)
read from the stats tables that it could be 0.9015.
Said the breaking load is 90.15%
I know this is incorrect please can you advise The probability that a randomly selected cable will have a breaking load greater breaking load than 6200 Newtons is 90%.
I'm working on a question now where I need to calculate the z value. which I have been able to but I'm calculating a value off the normal distribution that is on the left-hand side of the normal distribution curve and it needs to on the right side. As the value I'm looking into is higher than the mean!
I cannot figure out how I would turn this around. its only one independent event there's no replacement or other variables.
the question is:
A cable manufacturer tests the cables it produces to find the breaking load. Over many years this has been assumed to be normally distributed with a mean of 6000 Newtons and standard deviation of 155 Newtons. Calculate the probability that a single cable chosen at random, will have a breaking load greater than 6200 N. Z = 6200 -6000 /155 = 1.29
Then I've written a probability statement (P z>1.290) = P z>1.290)
read from the stats tables that it could be 0.9015.
Said the breaking load is 90.15%
I know this is incorrect please can you advise The probability that a randomly selected cable will have a breaking load greater breaking load than 6200 Newtons is 90%.
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