Answer:
Sample size should be atleast 617
Step-by-step explanation:
given that a 95% confidence interval for the mean of a population is to be constructed and must be accurate to within 0.3 unit.
i.e. margin of error <0.3
Std devition sample = 3.8
For 95% assuming sample size large we can use z critical value
Z critical = 1.96
we have
[tex]1.96 * std error <0.3\\1.96(\frac{3.8}{\sqrt{n} } )<0.3\\\sqrt{n} >24.83\\n>616.3634[/tex]
Sample size should be atleast 617 to get an accurate margin of error 0.3
