# Basic Arithmetic : Mean

## Example Questions

### Example Question #11 : Basic Statistics

Find the mean of the following set of numbers: 32, 23, 46, 52, 37.

Explanation:

To find the mean, or average, of a set of numbers, you first add all of the numbers together:

.

Then, you divide the sum by the total number of numbers, which in this set is 5 (i.e., there are 5 numbers in this set):

.

38 is the mean, or average, of this set of numbers.

### Example Question #31 : Statistics And Probability

This semester, Reese must take 4 exams for his algebra class. On his first 3 exams, he scored a 73, 79, and 83. What is the minimum score he must earn on his fourth exam to get an average of 80 or higher?

Explanation:

To calculate the average score, you must take the sum of Reese's scores and divide it by the number of tests he took (4). To get an average of 80, the sum of Reese's scores must be 320.

The sum of his first three test scores is 235.

Thus, Reese must earn a score of 85 on his fourth test

### Example Question #1463 : Algebra 1

Consider the following numbers:

42, 51, 62, 47, 38, 50, 54, 44

The value 48.5 represents:

The median

Both the mean and the median

The mean

Neither the median nor the mean

Both the mean and the median

Explanation:

First, calculate the mean. Sum the values and divide by the total number of values:

Next, determine the median. Reorder the values in ascending order:

38, 42, 44, 47, 50, 51, 54, 62

The median is the middle number. In this case, there is no "middle" number because we have an even number of values. Therefore, both 47 and 50 are the "middle". Average these numbers:

Therefore, 48.5 represents both the mean and median.

### Example Question #201 : Algebra Ii

Find the mean of the following numbers:

150, 88, 141, 110, 79

71

88

141

113.6

110

113.6

Explanation:

The mean is the average. The mean can be found by taking the sum of all the numbers (150 + 88 + 141 + 110 + 79 = 568) and then dividing the sum by how many numbers there are (5).

Our answer is 113 3/5, which can be written as a decimal.

Therefore 113 3/5 is equivalent to 113.6, which is our answer.

### Example Question #41 : How To Find Mean

Reginald has scores of {87, 79, 95, 91} on the first four exams in his Spanish class. What is the minimum score he must get on the fifth exam to get an A (90 or higher) for his final grade?

82

90

71

98

95

98

Explanation:

To find the fifth score, we need to set the average of all of the scores equal to 90.

Multiply both sides of the equation by 5.

Subtract 352 from both sides of equation.

### Example Question #1461 : Algebra 1

The mean of the following set is 8. What is ?

9

8

2

1

Cannot be determined

1

Explanation:

Let .

We know the mean is 8, and there are five values in the set, including the unknown .

Simplify.

Plug back into equation at top.

### Example Question #42 : How To Find Mean

If the average of  numbers is  and the average of  numbers is , what was the number added to increase the average?

Explanation:

If the average of  numbers is , then the sum is .

We also know the average of  numbers is . We can set-up an equation.

.

The expression in the numerator represents the sum. By cross-multiplying, we get

### Example Question #12 : Basic Statistics

If the average of  numbers is  and the average of  numbers is , what is the average of all the numbers?

Explanation:

To find the average of all the numbers, we need to find the sums from each average. Since the average of  numbers is , that means the sum is .

The average of  numbers is  means the sum is .

Then, the total sum is  which is the sum of all the numbers.

So to find average, we do  divided by  to get

### Example Question #13 : Basic Statistics

Find the mean for the following set of numbers:

, and

Explanation:

The mean is the same as the average. To find the mean, use the following formula:

### Example Question #11 : Basic Statistics

Find the mean for the following set of numbers:

, and