Answer:
a level of significance of 0.01 = 1%
Step-by-step explanation:
given
Z = 0.0001
mean μ=0.21 g/mi
variate x= 0.21 + 0.03
standard deviation σ= 0.05 g/mi.
N = sample population 20 cars
z = (x −μ )/[σ /√N ]
Z =
Z = 0.03/ (0.05/√20) = 0.03/0.0111
Z = 2.63 +- 0.0001
Z= 2.6301 or 2.6299
checking the level of significance table from a statistical book gives
a level of significance of 0.01 = 1%
therefore the null hypothesis is accepted.
Answer:
A. Your battery is likely defective since such poor performance is extremely unlikely.
Step-by-step explanation:
When the distribution is normal, we use the z-score formula.
In a set with mean and standard deviation
, the zscore of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
If X is more than two standard deviations from the mean, it is considered an unlikely outcome.
In this question, we have that:
Which of the following conclusions is the most appropriate given this information?
Lasted 400 hours, so X = 400.
4 standard deviations from the mean, so unlikely.
So the correct answer is:
A. Your battery is likely defective since such poor performance is extremely unlikely.