The Commercial Bank of Malaysia (population 1) advertises that 'our customers come

first' and claims that the waiting time for customer inquiries is the lowest. A sample of 60

of its customers waited an average of 9.5 minutes with a standard deviation of 3.5

compared to an average of 14 minutes with a standard deviation of 4 from a sample of 40

customers at Commercial bank of Thailand (population 2) branches. Assuming that the

population variances from both banks are equal, is there evidence that the mean waiting

time at the Commercial Bank of Malaysia is lower? Use 0.05 level of significance.