The mean price of all school uniform was RM 72 last year. A recent sample of 55 school uniforms produced a mean price equals to RM 75.22 with a variance of 16. One of college lecturers claims that the current mean price of all school uniform is greater than RM 81. Assume that the prices of all school uniforms have a normal distribution. The signicance level is 1%. (a) State the null and alternative hypotheses. (b) Obtain the critical value. (c) Determine the value of the test statistics. (d) Does the data provide sufcient evidence to support the claim? One hundred auto drivers were stopped by the police to see if they were wearing seat belts. Records of the results were given in the following table. Wearing seat belt Not wearing seat belt Men 54 41 Women 52 33 Test at the 2.5% significance level whether gender wearing seat belt are independent. A researcher wishes to see whether the mean of the heart rates (in beats per minutes} of smokers are different from the means of heart rates of people who do not smoke. The two samples are selected and the data are shown below. Using Elli = 0.05, is there enough evidence to support the claim