Question

1. On March 28 at 1:30 pm, I randomly selected 10 states and found the number of coronavirus cases in each of them.  This gave me an average of 939 cases with a standard deviation of 1543.  Assume the number of cases in each state is normally distributed.  Create a 90% confidence interval for the actual number of coronavirus cases in each state.

Answer 1

Solution :

Given that,

t /2,df = 1.833

Margin of error = E = t/2,df * (s /n)

= 1.833 * (1543 / 10)

Margin of error = E = 894

The 90% confidence interval estimate of the population mean is,

- E < < + E

939 - 894 < < 939 + 894

45 < < 1833

(45 , 1833)