Question 4 (11 marks)

Tex Tob Ltd is considering introducing new cleaning chemical for Timber floors. At present they are in the process of testing 3 different chemicals (A, B and C) which serve the same purpose.

To test the durability of these chemicals, five (5) newly build houses were cleaned with product A, five (5) with product B, and five (5) with product C. The process was repeated until the floor painting showed signs of deterioration.

The number of times each new house went through the cleaning before its floor paining deteriorated is shown in the table below.

Observations	Product A	Product B	Product C
1	30	34	28
2	32	30	28
3	28	28	29
4	35	35	30
5	29	36	32

Tex Tob Ltd must decide which chemical to market. The company requests your help to answer the following questions.

(a) Identify factor, treatment, experimental unit, and response variable

(b) Test the hypothesis with ANOVA to decide whether the three cleaning chemicals are equally effective?