To perform two sample hypothesis testing using normal distribution.
A study was conducted on the annual incomes of corporate trainers in the state of New York in metropolitan areas having a population less than 100,000 and in metropolitan areas having a population over 500,000. Some sample statistics are:
Sample Statistic

Population less than 100K

Population more than 500K

Sample Size

45

60

Sample Mean

$31,290

$31,330

Sample SD

$1,060

$1,900

Test hypothesis that the annual incomes of corporate trainers in areas of more than 500,000 are significantly more than those in areas of less than 100,000. Use the 5 percent level of risk.