Interquartile Range

Estimate median, quartiles, Interquartile range, Semi-interquartile range, Percentiles

Multiple Choice

What is the correct order for finding the Semi-interquartile Range (SIQR)?

• Find the median and upper quartile and divide by 2

• Find the median only then subtract 2

• Add the lower and upper quartile

• Find the difference between the lower and upper quartile and divide by 2

Multiple Choice

Quartiles are values that divide a data set into four equal parts.

• True

• False

Multiple Choice

if the ages of women in a book club are 34, 43, 45, 32, 38, 30, 44... what is the median?

• 35

• 228

• 38

• 76

Multiple Choice

What is the formula for finding the Interquartile Range (IQR)?

• Q3-Q1

• Q1-Q3

• Q2+Q3

• Q3/Q1

Multiple Choice

Jenny scored at the 99th percentile on a test.

How should this information be interpreted?

• Jenny scored better than 99% of people who took the test

• Jenny scored worse than 99% of people who took the test

• Jenny got 99% of the questions on the test right

• Jenny got 1% of the questions on the test wrong

Multiple Choice

Using the table, calculate the percentile rank of the score 65

• 36%

• 66%

• 63%

• None of these

Multiple Choice

What would be the correct approach in finding the Semi-interquartile Range?

12, 13, 14, 15, 15, 18, 20

• 18-15/2

• 20-13/3

• 18-13/2

• 13-18/2

Multiple Choice

The following statistics on the family income  in pesos are given below:

P25=4,500

P50=7,500

P75=10,800

P80=12,700

What percent of the families earn less than or equal to 4,500 pesos?

• 80%

• 50%

• 75%

• 25%