Mean

Step 1: Find the sum of the numbers

Step 2: Find how many numbers

There are numbers..

Step 3: Divide the sum by how many numbers they are...This division gives us the mean..

Step 1: Find the sum of the numbers

Step 2: Count how numbers there are:

There are numbers..

Step 3: Divide Sum by how many numbers

Step 1: Take the sum of all numbers in the set...

Step 2: Count how many elements are in the set...

There are numbers

Step 3: To find the mean, divide the sum by the number of elements..

The mean is

Step 1: Find the sum of the numbers in the set...

Step 2: Count how many numbers are in the set..

There are 10 numbers...

Step 3: Divide the total sum by how many numbers...

So,

Step 1: Find the sum of all the terms

Step 2: Count how many numbers are in the set

There are numbers.

Step 3: Divide the sum (Step 1) by how many numbers in the set (Step 2)

If the average of and is , then the sum must be .

If we add the sum of we get or .

To find the average of the three terms, we divide and to get .

Step 1: Find the sum of all numbers:

Step 2: Count how many numbers are in the question..

We have numbers.

Step 3: Divide sum by how many numbers

Step 1: Find the sum of all the numbers.

Step 2: Divide the sum by how many numbers there are. There are 11 numbers.

The mean (average) of all numbers above is .

The first ten prime numbers are . Prime numbers have two factors: and the number itself. Then to find mean, we add all the numbers and divide by .

There are two methods.

Method 1:

Since the average of consecutive number is , we can express this as:

Cross-multiply

Subtract on both sides then divide both sides by

Since we are looking for the second term, just plug into expression . That means answer is or .

Method 2:

Since the average of consecutive number is , this means the median is also . Consecutive means one after another and with each term having the same difference, we know the mean equals the median. Since there are terms, the median will have terms left and right of it. Then, the series will go . The second term is .