GED Math - Mean | Practice Hub

What is the mean for this set of data?

$\frac{2}{3}$ , $\frac{7}{8}$ , $\frac{6}{12}$

$\frac{49}{72}$

$\frac{72}{49}$

$\frac{49}{24}$

$\frac{24}{49}$

$\frac{24}{72}$

Explanation

In order to find the mean, we must first add up all of the numbers in the set, then divide the total number by how many numbers we have.

If you have a calculator, then adding these fractions should be easy. If you don't have a calculator, then we will add them up by hand.

Right now we can't add our fractions together, as they have no common denominator. We must convert all of these fractions to have the same denominator and then we can add them.

is a number that can have , , and in it, so we will use this number as our denominator. So we will multiply $\frac{2}{3}$ by , $\frac{7}{8}$ with , and $\frac{6}{12}$ with in order to have as the denominator. Make sure to multiply the numerator too!

$(\frac{2}{3})8+(\frac{7}{8})3+(\frac{6}{12})2$

$\frac{16}{24}+\frac{21}{24}+\frac{12}{24}=\frac{49}{24}$

Since we have fractions, we will divide $\frac{49}{24}$ by . This is the same as saying we are multiplying it by $\frac{1}{3}$ .

$\frac{\frac{49}{24}}{3}=\frac{49}{72}$

Our answer is $\frac{49}{72}$

John would like to have a 90 average for math for this semester. John received a 78, 89, 100 on three of his tests. What is the lowest grade he could receive on his last test in order for him to get a 90 average for the semester?

Explanation

In order for John to maintain a 90 average for the marking period, his total for four tests must be 360.

$\frac{360}{4} = 90$ or $90 \times 4 = 360$

If you add up the scores that he already received, he already has 267 points.

If you take the total of 267, which is the total amount of points for the three tests already taken and subtract it from the 360 points which is the total amount of points needed for a 90 average, he would need to get a 93 on his last test.

Veronica went to the mall and bought several small gifts for her sister's birthday. The prices of the items were the following:

$8, $10, $6, $3, $7, $10, $2, $5, $3

What is the mean price?

$10

Explanation

The meanof a set is the sum of all elements divided by the number of elements in the set:

$Mean = \frac{total\ sum}{#\ of\ elements}$

$Mean = \frac{8+10+6+3+7+10+2+5+3}{9}= \frac{54}{9} = 6$

The mean is $6.

Determine the mean of the numbers:

$\frac{11}{4}$

$\textup{There is no mean.}$

$\frac{29}{4}$

$\frac{1}{4}$

Explanation

The mean is the average of all the numbers in the set of data.

Add the numbers together and divide the sum by 4.

$\frac{5+(-9)+14+1}{4} = \frac{11}{4}$

The answer is: $\frac{11}{4}$

Find the mean of the numbers:

$\frac{9}{2}$

$\frac{3}{2}$

$\frac{41}{6}$

$\frac{9}{4}$

Explanation

The mean is the average of all the numbers.

Add all the numbers and divide the sum by 6.

$\frac{8+9+(-4)+(-3)+15+2}{6} = \frac{27}{6}$

Reduce this fraction.

The answer is: $\frac{9}{2}$

Determine the mean of the numbers:

$\textup{There is no mean.}$

Explanation

The mean is the average of all the number ins the data set.

Add all the numbers and divide the sum by four.

$\frac{3+(-8)+26+19}{4} = \frac{40}{4}$

The answer is:

Determine the mean of the numbers:

$\frac{5}{2}$

$\frac{15}{4}$

$\textup{There is no mean.}$

Explanation

The mean is the average of all the numbers in the data set.

Add all the numbers and divide the total by four.

$\frac{-1+(-2)+5+8}{4} = \frac{10}{4}$

Reduce the fraction.

The mean is: $\frac{5}{2}$

Determine the mean of the numbers:

$\textup{There is no mean.}$

Explanation

The mean is the average of all the numbers in the set of numbers.

Add the numbers and divide the quantity by four.

$\frac{-5+(-6)+9+14}{4} = \frac{12}{4} = 3$

The mean is:

In order for Joseph to pass his math class, he must have an average test score of . On his past four math tests he received the following scores: . What must he score on his fifth and final test in order to pass the class?

Explanation

Recall how to find the average of a set of numbers:

$\text{Average}=\frac{\text{Sum of all Terms}}{\text{Number of Terms}}$

We can then set up the following equation. Let be the score of the fifth test.

$75=\frac{58+81+72+71+x}{5}$

Solve for .

Joseph must score a on his next test to pass the class.

There are nine people in an elevator. They have an average weight of lbs. Two more people enter the elevator. They have an average weight of lbs. What is the new average weight of the group in the elevator? Round to the nearest hundredth of a pound.