AP Statistics 1.5 Graphical Representations for One Quantitative Variable- Exam Style Questions - MCQs - New Syllabus
Question
The histogram below shows magnitudes for 57 earthquakes.

Which interval will include the median magnitude for these 57 earthquakes?
(A) 1.0 to 1.5
(B) 1.5 to 2.0
(C) 2.5 to 3.0
(D) 3.5 to 4.0
(E) 6.5 to 7.0
▶️ Answer/Explanation
There are 57 earthquakes, so the median is the 29th observation when the data are ordered from smallest to largest.
\(\text{Median Position}=\frac{57+1}{2}=29\)
From the histogram, approximately 2 earthquakes fall in the interval 0.5–1.0 and about 17 fall in 1.0–1.5, giving a cumulative count of about 19. The next interval, 1.5–2.0, contains about 13 earthquakes, bringing the cumulative count to about 32.
Since the 29th observation falls within the interval 1.5–2.0, the median magnitude must lie in that class interval.
✅ Answer: (B)
Question

(B) The distribution is skewed to the right with most values between \(2\,\text{mg/l}\) and \(6\,\text{mg/l}\).
(C) The distribution is skewed to the left with most values between \(10\,\text{mg/l}\) and \(13\,\text{mg/l}\).
(D) The distribution is uniform from \(2\,\text{mg/l}\) to \(14\,\text{mg/l}\).
▶️ Answer/Explanation
The histogram has most of the observations concentrated at higher dissolved oxygen values, especially between about \(10\,\text{mg/l}\) and \(13\,\text{mg/l}\).
There are a few much smaller values extending toward the left side of the graph, from about \(2\,\text{mg/l}\) to \(6\,\text{mg/l}\). This creates a left tail.
Therefore, the distribution is skewed to the left, with its center around \(11\) to \(12\,\text{mg/l}\).
✅ Answer: (C)
Question
| Min | \(Q_1\) | Median | \(Q_3\) | Max | Mean | Std. Dev. |
|---|---|---|---|---|---|---|
| \(2.10\) | \(4.39\) | \(5.43\) | \(6.12\) | \(13.45\) | \(5.54\) | \(1.64\) |
(B) The box extends from \(2.10\) to \(13.45\), the median is at \(5.54\), and the whiskers extend to \(4.39\) and \(6.12\).
(C) The box extends from \(5.43\) to \(5.54\), the median is at \(4.39\), and the whiskers extend to \(2.10\) and \(13.45\).
(D) The box extends from \(4.39\) to \(5.43\), the median is at \(6.12\), and the whiskers extend to \(2.10\) and \(13.45\).
▶️ Answer/Explanation

A box plot is constructed using the five-number summary: minimum, \(Q_1\), median, \(Q_3\), and maximum.
From the table:
Minimum \(=2.10\)
\(Q_1=4.39\)
Median \(=5.43\)
\(Q_3=6.12\)
Maximum \(=13.45\)
Therefore, the box should extend from \(4.39\) to \(6.12\), with a median line at \(5.43\). The whiskers should extend to \(2.10\) and \(13.45\), since the problem says not to indicate outliers.
✅ Answer: (A)
