Question

John Glenn High School has approximately 1000 students. A survey randomly asked 20 students if they regularly buy lunch. Of those asked, 8 said yes. The table shows their answers when asked what their favorite food is and about how many times each month they buy it.

What portion of students purchased their favorite food more than four times a month. Write your answer as a simplified fraction.


b. What is the mean number of times a student bought their favorite food? Round your answer to the nearest tenth.



c. Predict how many students from John Glenn regularly buy lunch and purchase their favorite food more than four times a month. Round your answer to the nearest whole number.



d. What is the mean number of times that a student regularly buys a salad? Round to the nearest tenth.

Answer 1

Here we have the table for the 8 students that said yes.

a) Out of the 8 students, 5 purchased their favorite food more than four times a month.

The proportion will be p = 5/8, and this can not be simplified anymore because 5 is a prime number and 5 is not a factor of 8.

b) The mean time will be equal to the amount of each of the 8 purchased their favourite food divided by the total sample (8)

This is:

m = (6 + 4 + 3 + 8 +6 + 9 + 4 + 7)/8 = 5.875

c) Out of a sample of 20, 8 buy lunch regularly, this is; p1 = 8/20

The amount of students that regularly buy food will be:

p1*1000 = (8/20)*1000 = 400

And of those 400, 5/8 buy their favourite lunch more than 4 times per month:

(5/8)*400 = 250

d: The mean number of times that a student regularly buys salad.

We have 3 students that regularly buy salad (so we only do the math with those 3)

The mean is (8 + 6 + 7)/3 = 7

So for the students that regularly buy salad, the mean of times that the buy salad in a month is 7 times.