In: Statistics and Probability
The accompanying table contains data on the weight, in grams, of a sample of 50 tea bags produced during an eight-hour shift. Complete parts (a) through (d).
a. Is there evidence that the mean amount of tea per bag is different from 5.5 grams? (Use alphaαequals=0.10)
State the null and alternative hypotheses.
Upper H equals
5.55
Upper H ≠5.55
A). Determine the test statistic.
B). Find the p-value.
C). Construct a 90% confidence interval estimate of the population mean amount of tea per bag. Interpret this interval.
The 90% confidence interval is _ <= u <= _
Table:
5.64
5.43
5.43
5.41
5.55
5.33
5.55
5.43
5.52
5.42
5.58
5.41
5.53
5.52
5.55
5.62
5.55
5.45
5.44
5.49
5.48
5.39
5.47
5.61
5.51
5.33
5.66
5.28
5.48
5.54
5.76
5.59
5.44
5.56
5.59
5.52
5.32
5.48
5.53
5.57
5.62
5.43
5.43
5.26
5.55
5.64
5.49
5.57
5.68
5.35
n=50, = 5.55, = 0.10
Calculate mean and standard deviation for given data
We get,
= 5.4996, s= 0.105829
Ho: = 5.55
Ha: ≠ 5.55
a)
Calculate the test statistic
t = -3.3675
test statistics = -3.3675
b)
calculate the p-value using calculaor for two tailed test with
df= n-1 = 50-1 = 49
we get,
P-Value = 0.0015
c)
c= 90%
formula for confidenceinterval is
Where tc is the t critical value for c= 90% with df= n-1 = 50-1 =49
using t table we get
tc = 1.677
5.4745 5.5247
The 90% confidence interval is 5.4745 5.5247