Answer to Question #161927 in Statistics and Probability for Insyirah

Question

Table 4 shows the selling price of three different brands of sanitizer at based on 4 randomly selected 

supermarkets. At 80% confidence level, can we conclude there is a significant difference in mean

price of the three brands of sanitizer? Make your conclusion using the p- value approach, with the aid 

of Mic. Office EXCEL.

Table 4

Brand A (in RM) Brand B (in RM) Brand C (in RM)

10.00 12.00 9.80

9.50 11.50 10.40

10.00 10.40 10.30

11.10 11.00 10.80

Answer 1

H₀: the mean price of the three brands of sanitizer are same

H₁: at least one mean price of the three brands of sanitizer is different

The value of test statistic F = 3.64

P-value = 0.069

Since P-value < 0.2, so we reject the null hypothesis at 20% level of significance or at 80% level of confidence. The F value calculated 3.64 > critical value F(crit) of 1.93. The probability to obtain this result by chance (P-value) was calculated as 0.069 or 6.9 %. So, we are able to conclude that there was a significant difference in average between the three brands.