Answer:
The sample size is
Step-by-step explanation:
From the question we are told that
The sample standard deviation is
The mean difference of the two groups is
The standard error is
=>
Let assume that the confidence level is 95% hence the level of significance is
=>
So the critical value of obtained from the normal distribution table is
Generally the margin of error is mathematically evaluated as
Generally the sample size is mathematically represented as
=>
=>