A courier service advertises that its average delivery time is less than 6 hours for local deliveries. A random sample of times for 12 deliveries to...

A courier service advertises that its average delivery time is less than 6 hours for local deliveries. A random sample of times for 12 deliveries to an address across town was recorded. These data was shown here. Is this sufficient evidence to support the couriers's advertisement, at the 5% level of significance.

3.03

6.33

6.50

5.22

3.56

6.76

7.98

4.82

7.96

4.54

5.09

6.46