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Edexcel Statistics GCSE question !!

Hey guys how would you do this question ?
1. At regular intervals a sample of 10 packets is taken from the machine.The sample mean is calculated.The sample means are normally distributed with a mean of 1520g and a standard deviation of 4g. Between what limits would you expect 95% of the sample means to lie ?

Thanks
Reply 1
At GCSEs I assume that you just need to know that 95% of a normally distributed sample lies within 2 standard deviations of the mean. Which in this cases is within 8g of 1520 which is from 1512 to 1528.

At a-level you are expected to be able to use stats tables. But I think my first paragraph is all you need.
Original post by nerak99
At GCSEs I assume that you just need to know that 95% of a normally distributed sample lies within 2 standard deviations of the mean. Which in this cases is within 8g of 1520 which is from 1512 to 1528.

At a-level you are expected to be able to use stats tables. But I think my first paragraph is all you need.


Oh thank you :smile:

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