Question

1. on amazon, the following information is available for a book: book price, shipping price, author, publisher, number of pages, number of reviews, and the weight of the book. which of the following is the correct number of quantitative and categorical variables?

(a) 6 quantitative and 1 categorical
(b) 5 quantitative and 2 categorical
(c) 4 quantitative and 3 categorical
(d) 3 quantitative and 4 categorical
(e) 2 quantitative and 5 categorical

the cumulative frequency graph to the right shows
the number of hours reported, by teachers, of how
much sleep they get per night, on average.

1. what percent of teachers reported they

slept for 8 hours per night or less?

(a) 38% \t\t(d) 86%
(b) 67% \t\t(e) 95%
(c) 75%

1. if a teacher was told at the end of a sleep

study that they slept less than 60% of teachers,
approximately how many hours of sleep does that
teacher get per night?

(a) 2 \t\t\t(d) 6.4
(b) 3.1 \t\t\t(e) 7.3
(c) 3.8

1. what percent of teachers reported that

they get between 7 and 9 hours (the recommended
amount for adults according to the national
institute of health (nih.gov)) of sleep per night?

(a) 10% \t\t(d) 77%
(b) 15% \t\t(e) 92%
(c) 50%

Explanation:

Question 1

Step1: Identify variable types

Quantitative variables are numerical (can be measured/ counted), categorical are non - numerical (labels/names).
Book price, shipping price, number of pages, number of reviews, weight: 5 quantitative.
Author, publisher: 2 categorical.

Step1: Analyze cumulative frequency graph

The cumulative frequency graph (ogive) shows the percentage of teachers with sleep ≤ a certain number of hours. For 8 hours, we look at the y - value (cumulative relative frequency) at x = 8. From the graph, the cumulative frequency at 8 hours is 86%.

Step1: Interpret "less than 60% of teachers"

We need to find the x - value (hours of sleep) where the cumulative relative frequency is 60%. Looking at the graph, when the cumulative frequency is 60%, the corresponding hours of sleep is approximately 6.4.

Answer:

B. 5 quantitative and 2 categorical

Question 2