Answer:
Kindly check explanation
Step-by-step explanation:
Given the following :
True mean(μ) = 77.9
True standard = 20
Sample size (n) = 50
Sample mean (m) = 82.1
Sample standard deviation (s) = 18.6
The standard error (SE) :
SE = sample standard deviation / √sample size
SE = 18.6 / √50
SE = 2.6304372
SE = 2.63