1) A doctor claims that less than 75% of the patients that he performs a knee replacement surgery on return to work in the first 3 months after the operation. A sample of 50 patients that had a knee replaced by the doctor showed that only 34 of them returned to work within 3 months of the surgery. Test the doctor’s claim at the 0.05 level of significance.
2) A researcher wants to determine what proportion of all high school students plans to attend community college upon graduating. He has no idea of what the sample proportion will be. How large of a sample is required in order to be 90% sure that the sample proportion is off by
no more than 2%?
