The mean is the average of a set, or list of numbers.
If your test scores this year are 100 and 90, then your mean, or average, score is 95.
If you add up all the numbers in a set, and divide by the total number of items, you get the mean.
The grade on your report card is actually a mean of all of your homework and test grades.
Let's practice finding the mean of a set together.
Imagine that Sally runs a bakery.
She earned $186 on Monday, $215 on Tuesday, $263 on Wednesday, $192 on Thursday, and $204 on Friday. What is the mean of all her earnings?
To find the mean, first we add up all the numbers:
186 + 215 + 263 + 192 + 204 = $1,060
Then, we divide the sum by the total number of days.
We divide $1,060 by 5 days.
$1,060 ÷ 5 = $212
So the mean, or daily average, of Sally's earning is $212. 👏
Tip: To find the mean, just remember to:
Add then divide.
Let's try another example.
Find the mean of these numbers:
1250, 2160, 1639, 1730, 2300, 1640
What's the first thing to do?
Yes, add up all the numbers.
Tip: It helps to arrange the numbers in column form.
Our sum is 10,719.
Now, we divide the sum by the total number of items in the set, 6.
10,719 ÷ 6 = ?
We can find the quotient, or answer, using long division:
10,719 ÷ 6 = 1,786.5
This quotient is the mean, or average, of the set. ✅
Mean or average is the sum of the numbers divided by how many numbers are in the set.
To find the mean:
1️⃣ Add the numbers.
2️⃣ Divide by the total number of items in the set.
Excellent job learning about mean and average.
Now, complete the practice. Finding the mean, or average, is an important skill.