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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 theres 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

Z = 6200 -6000 /155 = 1.29

Then ive 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 theres 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

**newtons. Calculate the probability that a single cable chosen at random, will have a breaking load greater than 6200 N.***155*Z = 6200 -6000 /155 = 1.29

Then ive 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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