A large multi-branch bank is affiliated with both Mastercard and Visa credit cards. A random sample of 45 Mastercard clients found that their average month-end credit card balance was R922. For a random sample of 66 Visa card clients, their average month-end credit card balance was found to be R828.
Assume that the population of month-end credit card balances for Mastercard and Visa card clients is normally distributed, with population standard deviations of R294 for Mastercard clients and R336 for Visa card clients respectively. Establish at the 5% level of significance whether there is any significant difference in the average month-end credit card balances between Mastercard and Visa card clients.