Is there any difference between the proportion of Americans who wish they were rich and proportion of Canadians who wish they were rich? A random sample of 1,000 Americans showed that 550 wish they were rich, while random sample of 500 Canadians showed that 225 wished they were rich.
a. Determine a 97.5% confidence interval for the difference between population proportions who wish they were rich.
Note: Express your answer to 4 decimal places of accuracy.