A sample of 10 sheets of paper has been selected randomly from a ream (500 sheets) of paper. The width and length of each sheet of the sample were measured, with the following results:

(a) Calculate the sample mean width and its sample standard deviation, and the sample mean length and its sample standard deviation.
(b) Give the expected error in the width and length at the 95% confidence level.
(c) Calculate the expected ream mean area from the width and length.

(d) Calculate the area of each sheet in the sample. Calculate from these areas the sample mean area and the standard deviation in the area.
(e) Give the expected error in the area from the results of part d.

Transcribed Image Text:

Sheet number Width (in.) Length (in.) 1 8.50 11.03 10.99 8.48 3 8.51 10.98 8.49 11.00 11.01 8.50 8.48 11.02 8.52 10.98 8.47 11.04 8.53 10.97 10 8.51 11.00 4)