Answer:
The absolute error of the measurement is 0.25 inches
Step-by-step explanation:
we know that
The absolute error of a measurement is equal to one half the unit of measure.
In this problem we have
7.5 inches
The measurement is given by 0.5 inches
So
the absolute error of this measurement is
Therefore
the exact measurement could be between
7.5 (+/-) 0.25 in
That is, between 7.25 in and 7.75 in
Answer:
The sample size should be approximately 151.
Step-by-step explanation:
We are given the following in the question:
Population mean, μ = 100
Population standard deviation, σ = 15
We have to evaluate the sample size, n.
Alpha, α = 0.10
Confidence interval:
Putting the values, we get,
Thus, the sample size should be approximately 151.