2 In a recent year the most popular colors for light trucks

2. In a recent year, the most popular colors for light trucks were white, 30%; black, 17%; red, 14%; silver, 12%; gray, 11%; blue, 8%; and other, 8%. A survey of light truck owners in a particular area revealed the following At a 0.05 do the proportions differ from those Stated? White Black Red Silver Gray Blue other 32 30 30 22 15 6 45

Solution

For this let us do chi square test to establish whether the actual is the same as the proportion stated.

H0: The trucks have the colour as stated.

Ha: The trucks have different colours than stated.

Two tailed chisquare test

Let us prepare contingency table.

Degree of freedom =6

p value = 0.9999

As p value is much higher than alpha 0.05, conclusion is accept H0.

The observed are the same as proportions stated.

	White	Black	Red	Silver	Gray	Blue	Other	total
Obs	45	32	30	30	22	15	6	180
Expected	54.00	30.60	25.20	21.60	19.80	14.40	14.40	180
percent	30	17	14	12	11	8	8	100
Chi square	0.091057