Mean

SAT Subject Test in Math I · Learn by Concept

Help Questions

SAT Subject Test in Math I › Mean

1 - 10

What is the mean of: $\{2,5,10,77,241,33\}$ ?

$61.\overline{33}$

CORRECT

Explanation

Step 1: Find the sum of the values...

Step 2: Find how many numbers are given...

There are numbers.

Step 3: To find the mean, divide the sum by how many numbers....

$\frac {368}{6}=61.\overline{33}$

Karen wants to get an average of 92% at the end of the semester in her class. She has 1 test left to take before the semester is over to raise her average. If she recieved an 88%, 87%, 95%, and 93% on her tests what does she need to recieve on her last test to obtain the 92% average?

97%

CORRECT

93%

100%

95%

Explanation

For this question we need to set up an equation to find the mean, set it equal to our desired mean of 92 and solve for our missing test value.

$\frac{93+88+87+95+x}{5}=92$

From here we perform algebraic procedures to simplify the equation

$\frac{363+x}{5}=92$

Find the mean of the following set:

CORRECT

Explanation

Another word for mean is average. To find the average of this set of numbers, add them up, then divide by the amount of numbers in the set. In this case there are 5 numbers in the set, meaning we will divide our answer by 5.

$\frac{6+91+12+31+12}{5}=\frac{152}{5}=30.4$

In terms of , what is the mean of $f-1, f+2, f-6, f-5, \text{ and }f+15$ ?

CORRECT

Explanation

Recall how to find the mean:

$\text{Mean/Average}=\frac{\text{Sum of all values}}{\text{Number of values}}$

$\text{Mean}=\frac{(f-1)+(f+2)+(f-6)+(f-5)+(f+15)}{5}=\frac{5f+5}{5}=f+1$

Determine the mean of the numbers:

$-\frac{11}{4}$

CORRECT

$\frac{11}{4}$

$\frac{29}{4}$

$\textup{The mean does not exist.}$

Explanation

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

Add the numbers provided.

Divide this value by four.

$\frac{-11}{4}$

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

Find the mean of: $\{2,2,4,4,6,6,8,8,12,12,7,6,5,4,3,3,3,3,3,33,41\}$

$8.\overline {33}$

CORRECT

Explanation

Step 1: Find the sum of all the numbers...

$2+2+4+4+6+6+8+8+12+12+7+\6+5+4+3+3+3+3+3+33+41=175$

Step 2: Count how many numbers there are...

There are elements.

Step 3: Divide the total sum by the number of elements...

$\frac {175}{21}=8.\overline {33}$

Find the mean of the following set:

CORRECT

Explanation

Another word for mean is average. To find the average of this set of numbers, add them up, then divide by the amount of numbers in the set. In this case there are 7 numbers in the set, meaning we will divide our answer by 7.

$\frac{41+38+27+42+35+38+44}{7}=\frac{265}{7}=37.9$

On her past five tests, Julie scored $100, 90, 67, 89, \text{ and } 78$ . What was the mean of her scores?

CORRECT

Explanation

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

$\text{Mean}=\frac{\text{Sum of all values}}{\text{Number of Values}}$

$\text{Mean}=\frac{100+90+67+89+78}{5}=84.8$

Jack has an average of on four exams. If he has one more exam and he wants to bump his average up by points, what must he score to get that average he wants?

CORRECT

Explanation

First, we need to find the total number of points for his fourth exam. That would be or . The reason we do this is because we can calculate his point total with the new average and determine his final score by taking the difference. So . We subtract and to get as our answer.