Data Analysis and Statistics Flashcards

The box plot for a data set shows: min=10, Q1=20, median=30, Q3=45, max=60. What is the interquartile range (IQR)?

Answer: 25

IQR = Q3 - Q1 = 45 - 20 = 25.

A line graph shows a city's population grew from 50,000 in 2010 to 75,000 in 2020. What is the percent increase?

Answer: 50%

(75,000 - 50,000)/50,000 × 100 = 25,000/50,000 × 100 = 50%.

Which type of graph is best for showing the frequency distribution of continuous data?

Answer: Histogram

Histograms display continuous data in intervals, making them ideal for frequency distributions.

If the mean of a data set is 20 and a value of 40 is added, the mean will:

Answer: increase

Adding a value (40) above the current mean (20) will pull the mean upward.

A two-way table shows 120 students: 60 like science, 50 like math, and 20 like both. How many like neither?

Answer: 30

Using inclusion-exclusion: 60 + 50 - 20 = 90 like at least one. 120 - 90 = 30 like neither.

In a data set, the standard deviation is 0. This means:

Answer: All values are equal

A standard deviation of 0 means all values in the data set are identical.