Problem 1:

A report states that on average Moroccan boys (12-18 years old) get a haircut 5.8 times a year. An independent researcher randomly selected 20 boys (12-18 years old) and obtained these data.

3 2 1 3 7 2 9 4 6 6

8 0 5 6 4 2 1 3 4 1

At = 0.05, can it be concluded that the average is still 5.8 visits per year?(Hint: use the t test)

Problem 2:

A journalist claims that the mean salary of middle class citizens in Casablanca is 9,600 MAD. To see how this compares to his neighborhood, a student surveyed 28 randomly selected middle class people and found that their mean income is 8,850 MAD. If the standard deviation for Casablanca middle class citizens is 1,000 MAD, can the student conclude that there is a difference at = 0.10?

Problem 3:

I was found that 85.6% of students at IUL worldwide are enrolling to undergraduate program. A random sample of 50 students from IUL Morocco revealed that 42 of them were enrolled in undergraduate program. Is there evidence to state that the proportion of IUL Morocco differs from the IUL Morocco proportion? Use = 0.05

Problem 4:

A research showed that the average rate of renting a car in Marrakech is 884.2 dhs and the average in Casablanca is 806.1 dhs. The mentioned data was obtained by taking two samples of 50 rental agencies in each city and that the standard deviation of the population is 56.2 dhs and 48.3 dhs of Marrakech and Casablanca respectively. At = 0.05, can it be concluded that there is a difference in the rates of both cities?