Question

1. Three hundred people from a sample of 350 were using face coverings or masks during an event. Estimate the percent of the population, where that sample came from, who were using face coverings or masks. Use a 90% confidence interval for that estimate.
2. A new vaccine is being developed by a medical research group. To test the variability of the new vaccine, a random sample of 9 people were given the vaccine and the protection time was recorded for each person. The results were: 4 months, 4.5 months, 6 months, 4.7 months, 6.2 months, 4.7 months, 5.2 months, 4.9 months, and 4.2 months. Estimate the population standard deviation using a 90% confidence interval.

Answer 1