# Statistics

posted by .

A packaging device is set to fill detergent power packets with a mean weight of 5 Kg. The standard deviation is known to be 0.01 Kg. These are known to drift upwards over a period of time due to machine fault, which is not tolerable. A random sample of 100 packets is taken and weighed. This sample has a mean weight of 5.03 Kg and a standard deviation of 0.21 Kg. Can we calculate that the mean weight produced by the machine has increased? Use 5% level of significance.

• Statistics -

Z = (mean1 - mean2)/standard error (SE) of difference between means

SEdiff = ?(SEmean1^2 + SEmean2^2)

SEm = SD/?(n-1)

Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion related to that Z score.

• Statistics -

244

• Statistics -

X-x/q

## Similar Questions

1. ### Statistics

Machines are used to pack sugar into packets supposedly containing 1.20 kg each. On testing a large number of packets over a long period of time, it was found that the mean weight of the packets was 1.24 kg and the standard deviation …
2. ### statistics

question- a packaging device is set to fill detergent powder packets with a mean weight of 5 kg .the standered deviation is known to be 0.01kg.these are known to drift upward over a period of time due to machine fault,which is not …
3. ### statistics/probability

QUESTION- machines are used to pack sugar into packets supposedly containing 1.20kg each.on testing a large number of packets over a long perodof time ,it was found that the mean weight of the packets was 1.24kg and the standard deviation …
4. ### statistics

Machines are used to pack sugar into packets supposedly containing 1.20 kg each. On testing a large number of packets over a long period of time, it was found that the mean weight of the packets was 1.24 kg and the standard deviation …
5. ### SMU

Ans:- Machines are used to pack sugar into packets supposedly containing 1.20 kg each. On testing a large number of packets over a long period of time, it was found that the mean weight of the packets was 1.24 kg and the standard deviation …
6. ### Statistics

The amount of fill(weight of contents)put into a glass jar of spaghetti sauce is normally distributed with mean=850g and standard deviation=8g.the probability that a random sample of 24 jars has a mean weight greater than 848g is?
7. ### marketing research

A packaging device is set to fill detergent power packets with a mean weight of 5 Kg. The standard deviation is known to be 0.01 Kg. These are known to drift upwards over a period of time due to machine fault, which is not tolerable. …
8. ### statistics

a manufacturer of detergent claims that the contents of the boxes in the market weigh on average at least 16 oz.. the distribution of weights is known to be normal with a standard deviation of 0.4 oz. to test the claim of the manufacturer …
9. ### statistics

a packaging device is set to fill detergent powder packets with a mean weight of 5kg.The standard deviation is known to be .01kg.these are known to drift upwards over a period of time due to machine fault which is not tolerable. A …
10. ### quantitative methods

a packing device is set to fill detergent powder packet with a mean weight of 5 kg . The standard deviation is known to be 0.01 kg. these are known to drift upwards over a period of time due to machine fault, which is not tolerable. …

More Similar Questions