Queries to a call centre about mobile phone accounts are logged and the time taken to answer each query is recorded. The data represent the time (in minutes) to answer samples of 20 queries made to two different call centre teams. Assuming that the population variances for both teams are equal. Is there evidence of a difference in the mean query answer time between the two call centre teams? (Use α=0.05). Time to answer queries (minutes)
Team I 1.58 1.75 2.78 2.85 1.52 1.6 4.15 3.97 2.48 3.1 1.02 3.53 0.93 1.6 0.8 4.05 6.32 3.93 5.45 0.97
Team II 7.55 3.75 2.1 1.1 0.6 1.52 3.3 2.1 2.58 4.02 3.75 0.65 1.92 1.6 1.53 4.23 3.08 1.48 1.65 4.72