A random sample of 10 miniature Tootsie Rolls was taken from a bag. Each piece was weighted on a very accurate scale. The results in grams were:
a. 3.087
b. 3.131
c. 3.241
d. 3.241
e. 3.270
f. 3.353
g. 3.400
h. 3.411
i. 3.437
j. 3.477
a) Construct a 90 percent confidence interval for the true mean weight.
b) What sample size would be necessary to estimate the true weight with an error of ± 0.03 grams with 90 percent confidence?
c) Discuss the factors which might cause variation in the weight of Tootsie Rolls during manufacture.