Consider the grouped data analysis for the number of cigarettes consumers smoke weekly.

Classes                               frequency

1 - 5                                   10

6 - 10                                11

11 - 15                               7

16 - 20                               4

21 - 25                               2

What is the distribution of the number of cigarettes smoked weekly?  What does it tell you?

(8)If we are to randomly select a smoker, what is the probability that the smoker will smoke at most 10 cigarettes a week?

(7) Distribution is right skewed and it means that majority of people were smoking 1 to 10 cigarettes weekly

(8) Probability of at most 10 cigarettes a week is 0.6176

Step-by-step explanation

(7) We can see that the frequency is maximum for first few classes as compared to last classes, which has minimum frequency.

If we draw a histogram, then long bars will be observed on left end and short bars on the right end, this makes the histogram skewed to the right.

It tells us that majority of people were smoking 1 to 10 cigarettes  weekly

(8) total frequency = 10 + 11 + 7 + 4 + 2 = 34

Frequency for at most 10 cigarettes a week = 10 + 11 = 21

Probability of at most 10 cigarettes a week = (Frequency for at most 10 cigarettes a week)/(Total frequency)

= 21/34

= 0.6176