Question

the noon-time barometer readings for 7 days: 28.5, 29.6, 30.1, 29.4, 26.5, 22.7, and 26.8. find the interquartile range of the data.

\\( \bigcirc \text{ iqr} = 2.5 \\)
\\( \bigcirc \text{ iqr} = 3.1 \\)

Explanation:

Order the data set

Using the Ordering Numbers knowledge point

$$ 22.7, 26.5, 26.8, 28.5, 29.4, 29.6, 30.1 $$

Find the median

Using the Quartiles of Data knowledge point

$$
LATEXBLOCK0
$$

Find the first and third quartiles

Using the Quartiles of Data knowledge point

$$
LATEXBLOCK1
$$

Calculate the interquartile range

Using the Interquartile Range knowledge point

$$ \text{IQR} = Q_3 - Q_1 = 29.6 - 26.5 = 3.1 $$

Answer:

• (A) IQR = 2.5
• (B) IQR = 3.1 (Correct answer)