If a population has a standard deviation σ
of 25 units, what is the standard error of
the mean if samples of size 100 are
selected?
SEm = SD/√n
To find the standard error of the mean, you need to divide the standard deviation of the population by the square root of the sample size.
In this case, the standard deviation of the population (σ) is given as 25 units, and the sample size is 100.
To calculate the standard error of the mean:
1. Take the square root of the sample size: √(100) = 10
2. Divide the standard deviation by the square root of the sample size: σ / √(sample size)
= 25 / 10 = 2.5 units
Therefore, the standard error of the mean for samples of size 100 from this population is 2.5 units.