Do you know what a mode is? When you have a set of data, you can figure out the mode. Let's think about Tania and her carrots.

Here is Tania’s data about the number of carrots picked each week over nine weeks of harvest.

2, 8, 8, 14, 9, 12, 14, 20, 19, 14

What number of carrots was picked most often?

**This is what you will learn in this Concept. You will learn about the mode.**

### Guidance

The ** mode** of a set of data is simply the number that occurs most often. When we put our data in numerical order, it becomes easy to see how often each of them occurs.

Let’s look at the data set below.

61, 54, 60, 59, 54, 51, 60, 53, 54

**First, we put the data in numerical order.**

51, 53, 54, 54, 54, 59, 60, 60, 61

**Now we look for any numbers that repeat.**

Both 54 and 60 appear in the data set more than once. Which appears more often?

**54 repeats the most times. That is our mode.**

**Our answer is 54.**

**What if a data set doesn’t have a repeating number?**

If no number occurs more than once, or if numbers appear in the set the same number of times, the set has no mode.

22, 19, 19, 16, 18, 21, 30, 16, 27

**In the set above, both 16 and 19 occur twice.** No number in the set happens the *most* often, so **there is no mode for this set.**

**How can we use the mode to analyze data?**

Because it is the number that occurs most often in a data set, we know that it is the most frequent answer to our question or result of our experiment.

Now let's practice. Find the mode of each data set.

#### Example A

2, 4, 4, 4, 6, 7, 8, 8, 10, 10, 11, 12

**Solution: 4**

#### Example B

5, 8, 9, 1, 2, 9, 8, 10, 11, 18, 19, 20

**Solution: 9**

#### Example C

12, 12, 5, 6, 7, 11, 23, 23, 67, 23, 89, 23

**Solution: 23**

Now back to the original problem. Here is Tania’s data about the number of carrots picked each week over nine weeks of harvest.

2, 8, 8, 14, 9, 12, 14, 20, 19, 14

Which number of carrots was harvested the most often?

To answer this question, we need to reorder the data to find the mode or the number that occurs the most often.

2, 8, 8, 9, 12, 14, 14, 14, 19, 20

**The number 14 occurs the most often, that is the mode of this data set.**

### Vocabulary

- Mean
- the average of a set of numbers. The mean gives us a good overall assessment of a set of data.

- Maximum
- the greatest score in a data set

- Minimum
- the smallest score in a data set

- Median
- the middle score in a data set

- Mode
- the number or value that occurs most often in a data set

### Guided Practice

Here is one for you to try on your own.

Suppose the data below shows how many people visit the zoo each afternoon.

68, 104, 91, 80, 91, 65, 90, 91, 70, 91

**Answer**

We can see that 91 occurs most often in the set, so we know 91 is the mode.

This number helps us approximate how many people visit the zoo each afternoon because it was the most frequent number.

### Video Review

James Sousa, Mean, Median & Mode

### Practice

Directions: Identify the mode for the following sets of data.

1. 2, 3, 3, 3, 2, 2, 2, 5, 6, 7

2. 4, 5, 6, 6, 6, 7, 3, 2

3. 23, 22, 22, 24, 25, 25, 25

4. 123, 120, 121, 120, 121, 125, 121

5. 678, 600, 655, 655, 600, 678, 600, 600

6. 4, 5, 4, 5, 3, 3

7. 6, 7, 8, 3, 2, 4, 4, 7, 7, 7

8. 11, 10, 9, 13, 14, 16, 11, 10, 11

9. 21, 23, 25, 22, 22, 27

10. 27, 29, 29, 32, 30, 32, 31

11. 34, 35, 34, 37, 38, 39, 39, 34, 34

12. 43, 44, 43, 46, 39, 50, 43, 43

13. 122, 100, 134, 156, 144, 110, 110

14. 224, 222, 220, 222, 224, 224

15. 540, 542, 544, 550, 548, 547, 547, 550, 550, 548