LT

Test: Quartiles and box plots

Dynamic tasks on medians, quartiles, interquartile range, outliers and reading box-and-whisker plots.

Question qty: 10
Duration in minutes: 18
Start »

Time left: 00:00:00

Finish the test
List of tests
Start over

Sample questions

  • Find the first quartile Q1: duomenys.
  • What median is shown in the box plot? diagrama
  • Find the second quartile Q2: duomenys.
  • Find the third quartile Q3: duomenys.
  • Approximately what percentage of data lies between the first and third quartiles?
  • The first quartile is q1 and the third is q3. Find the interquartile range.
  • Set A has interquartile range a, and set B has b. Which set has more spread in its middle 50%?
  • For data with Q1 = q1 and Q3 = q3, using the 1.5·IQR rule, is x an upper outlier?

Quartiles and box plots

For ordered data, the median Q2 divides the values into two parts, while Q1 and Q3 divide them into quarters. The interquartile range IQR = Q3 − Q1 measures the spread of the middle 50% and is less sensitive to extreme values than the full range.

Plots and outliers

A box plot displays the minimum, Q1, median, Q3 and maximum, with outliers shown separately under the chosen convention. A common outlier rule is below Q1 − 1.5IQR or above Q3 + 1.5IQR. Compare both centre and spread when interpreting groups.

Related mathematics tests

Histograms and grouped data

Dynamic tasks on reading histograms, interval frequencies, relative and cumulative frequencies, and estimated means.

Solve: Histograms and grouped data

Exchange rates and compound interest

Dynamic tasks on currency conversion, rate comparison, compound interest, loan fees and financial offers.

Solve: Exchange rates and compound interest

Pythagoras in solids

Dynamic tasks on space diagonals, cone slant height, pyramid apothem, sphere area and volume.

Solve: Pythagoras in solids

Vectors

Dynamic tasks on vector coordinates, sum, difference, scalar multiplication, magnitude and equality.

Solve: Vectors