The frequency table below shows the hourly wages of 22 factory workers. How many are paid $10.50 per hour or more?
Hourly Wage
Interval
Frequency
$7.50–$8.49
1
$8.50–$9.49
4
$9.50–$10.49
6
$10.50–$11.49
7
$11.50–$12.49
4
A. 7
B. 11
C. 17
D. 18
The number of workers paid $10.50 per hour or more is the sum of the frequencies in the $10.50–$11.49 and $11.50–$12.49 intervals: $$7+4=\boxed{11}.$$ Answer: \boxed{11}.
Researchers at Jackson Hospital asked 40 randomly selected patients about their sleep habits. Sixteen reported sleeping 8 hours or more each night. If there are 700 patients in the hospital, estimate the number of patients who sleep 8 hours or more each night.
A. 140
B. 160
C. 180
D. 280
We can set up a proportion to estimate the number of patients who sleep 8 hours or more each night:
$$\frac{16}{40} = \frac{x}{700}$$
where $x$ is the number of patients who sleep 8 hours or more each night.
To solve for $x$, we cross-multiply and get:
$$16 \cdot 700 = 40 \cdot x$$
Dividing both sides by 40, we have:
$$x = \frac{16 \cdot 700}{40} = 280$$
Therefore, we estimate that 280 patients in the hospital sleep 8 hours or more each night. The answer is $\boxed{\textbf{(D) }280}$.
A sports reporter said that 2 out of every 3 people he talked to at a hometown baseball game named baseball as their favorite sport. The reporter claimed that baseball was the most popular sport in town. Which of the following explains why the reporter's claim might not be true?
A. Only sixty-six percent of the people chose baseball.
B. The reporter only talked to people at a baseball game.
C. Only the people that the reporter talked to were counted.
D. The reporter did not say what sport the other people chose.
The reporter's claim might not be true because he only talked to people at a hometown baseball game, which might not be representative of the town as a whole. In other words, the people at the baseball game might be more likely to choose baseball as their favorite sport compared to the general population of the town.
Therefore, choice $\boxed{\textbf{(B)}}$ is the correct explanation of why the reporter's claim might not be true.
Suppose that you want to compare the average cost of a gallon of milk to the average cost of a gallon of gasoline in the U.S. over 20 years. Which type of display would be the best choice?
A. a double line graph
B. a double bar graph
C. a stem-and-leaf plot
D. a frequency table
Since we want to compare numerical data (cost) between two different categories (milk versus gasoline) over time, the best choice would be a double line graph, represented as two lines on the same graph with different colors or patterns. This type of graph is commonly used to display changes or trends over time and allows for easy comparison between the two categories.
Therefore, the correct answer is $\boxed{\textbf{(A)}\ \text{a double line graph}}$.
The stem and leaf plot below shows the number of points scored in each basketball game a team played during a season. In how many games were more than 40 points scored?
Stem
Leaf
6
1 6 7
5
2 2 8
4
4 5 8 9
3
0 2 6 6 6
2
0 8
A. 4
B. 6
C. 7
D. 10
We need to count the number of games where the score was more than 40 points. From the given stem-and-leaf plot, we can see that the scores are arranged as follows:
- 61, 67, 68
- 52, 58
- 44, 45, 48, 49
- 30, 32, 36, 36, 36
- 20, 28
Thus, there were $\boxed{\textbf{(A)}\ 4}$ games in which more than 40 points were scored.
The stem-and-leaf plot shows the height, in inches, of the players on two different basketball teams. How many players on each team are less than 70 inches tall?
Heights of Players
In inches
Austin College Barton College
Leaf
Stem
Leaf
6 7 8 8 9
6
4 6 8
1 1 2 6
7
1 1 1 3 4 5
1
8
2
A. Austin College, 4; Barton College, 6
B. Austin College, 5; Barton College, 7
C. Austin College, 5; Barton College, 3
D. Austin College, 9; Barton College, 9