Question

Paint 1	Paint 2	Paint 3	Paint 4
128	144	133	150
137	133	143	142
135	142	137	135
124	146	136	140
141	130	131	153

Four different paints are advertised as having the same drying time. To check the manufacturer’s claim, five samples were tested for each of the paints. The time in minutes until the paint was dry enough for a second coat to be applied was recorded. The following data were obtained.

At 5% level of significance, test to see whether the mean drying time is the same for each of the paint.

H_0:

H_a:

Answer 1