Mode of a data set

Count how often each value appears. The most frequent value is the mode — or values, plural, when two or more tie. When every value appears exactly once, the data set has no mode.

01 Mini-Lesson Video

▸ VIDEO COMING SOON

A short walkthrough explaining what you need to know and how to solve this question type lands here once it's recorded.

02 What This Looks Like on ALEKS

ALEKS randomizes the numbers each attempt, but the question shape stays the same. Here are three example versions you might see.

Siblings per student v1

The following list gives the number of siblings for each of 8 students:

1, 1, 3, 3, 3, 0, 2, 1

Find the mode(s) of this data set. If there is more than one mode, write them separated by commas. If there is no mode, click "No mode."

Pets per household v2

A survey of 10 households in a neighborhood asked how many pets they own:

2, 0, 1, 2, 3, 1, 0, 2, 4, 1

Find the mode(s).

Quiz scores v3

A short quiz was given to 9 students. Each scored a different number out of 10:

7, 9, 6, 8, 5, 4, 10, 3, 2

Find the mode(s). If there is no mode, click "No mode."

Heads up: Your ALEKS version will use different numbers. The numbers in the practice below are different too — that way you're exercising the move, not memorizing one answer.

03 How to Solve It

mode = value(s) that appear most often
tie → bimodal · all unique → no mode

The mode is about frequency, not size. Tally each value, then read off the most frequent.

Tally how often each value appears.

Data: 1, 1, 3, 3, 3, 0, 2, 1. Counting:

0 \to 1 time 1 \to 3 times 2 \to 1 time 3 \to 3 times

Identify the most-frequent value(s).

1 and 3 are tied at three occurrences each — more than any other value. The data set has two modes:

modes = 1, 3

This is called bimodal. ALEKS expects both values, separated by a comma.

▸ COMMON SLIPS(1) Picked the largest value. The mode is the most frequent, not the largest. 3 is the biggest number here, but 1 ties with 3 for frequency. (2) Skipped the tie. When two values are tied for most frequent, both are modes. List them both. (3) Listed every value that appears. Only the values with the highest count are modes. Single appearances don't count.

04 Practice — Step by Step

Try a different list. Tally first, then read off the most-frequent value(s).

Find the mode(s) of this data set.

10 households surveyed for number of pets: 2, 0, 1, 2, 3, 1, 0, 2, 4, 1. What is the mode?

mode =

Now a no-mode data set.

9 students each scored a different number on a quiz: 7, 9, 6, 8, 5, 4, 10, 3, 2. What is the mode? (Type 0 for "No mode.")

mode =

▸ NICE WORK

You've walked through the whole problem.

That's the move. ALEKS will give you a different version with different numbers — but the steps are the same.

Q1 Q3