Basic Statistics - Basic Math
Card 1 of 344
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?
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?
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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.
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.
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Find the mean of the following numbers:
150, 88, 141, 110, 79
Find the mean of the following numbers:
150, 88, 141, 110, 79
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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.
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.
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What is the mean of 44, 22, 134, and 200?
What is the mean of 44, 22, 134, and 200?
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To find the mean, you must add all of the numbers together and divide by the amount of numbers. In this case there are four numbers so, we must deivide the total sum by 4.
To find the mean, you must add all of the numbers together and divide by the amount of numbers. In this case there are four numbers so, we must deivide the total sum by 4.
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Calculate the mean of the following numbers: 11, 13, 16, 13, 14, 19, 13, 13
Calculate the mean of the following numbers: 11, 13, 16, 13, 14, 19, 13, 13
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First, calculate the sum of all of the numbers.
Next, divide by the total number.
First, calculate the sum of all of the numbers.
Next, divide by the total number.
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The class average in a class of 15 is 86%. If one additional student earns a 100% in the class, what is the new class average.
The class average in a class of 15 is 86%. If one additional student earns a 100% in the class, what is the new class average.
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We can treat this as if the entire class had exactly 86% as their average, so the new average is:
We can treat this as if the entire class had exactly 86% as their average, so the new average is:
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What is the mean of the following numbers?
88,99,31,47,68,27
What is the mean of the following numbers?
88,99,31,47,68,27
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To find the mean you add all of the numbers together and divide it by the amount of numbers. In this case there are six numbers so 
The answer is 
.
To find the mean you add all of the numbers together and divide it by the amount of numbers. In this case there are six numbers so
The answer is
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Sally's algebra grade depends on three unit tests and a final exam. The grade for the final exam is weighted to equal the grade of two unit tests. What is the minimum grade that Sally must get on her final exam in order to have a class average of 
or above for the course, if her unit test scores are 
, 
, and 
Sally's algebra grade depends on three unit tests and a final exam. The grade for the final exam is weighted to equal the grade of two unit tests. What is the minimum grade that Sally must get on her final exam in order to have a class average of 
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The course grade average is calculated by using Sally's three test scores and final exam. student must score at least an average of 
; therefore we can write the following:
Given that the average is calculated using three test scores and a final weighted as two regular tests, we can write the following equation.
Let's use these equations to construct an inequality where we will substitute in our known values and let a variable, 
, equal the final score needed to earn an a 
or above.
Sally needs to at least score a 
on the final to score 
or above.
The course grade average is calculated by using Sally's three test scores and final exam. student must score at least an average of 
Given that the average is calculated using three test scores and a final weighted as two regular tests, we can write the following equation.
Let's use these equations to construct an inequality where we will substitute in our known values and let a variable, 
Sally needs to at least score a 
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Find the mean of the following set of numbers: 32, 23, 46, 52, 37.
Find the mean of the following set of numbers: 32, 23, 46, 52, 37.
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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.
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.
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Consider the following numbers:
42, 51, 62, 47, 38, 50, 54, 44
The value 48.5 represents:
Consider the following numbers:
42, 51, 62, 47, 38, 50, 54, 44
The value 48.5 represents:
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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.
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.
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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?
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?
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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
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
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For her calculus class, Marie has scored 
, 
, and 
on three of her tests so far. What is the minimum score Marie needs to receive on her 4th test in order to have an average of 
?
For her calculus class, Marie has scored
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To find the average of a set of numbers, add up the individual values and divide by the total number of values you have.
For the test scores, we can set up the following equation with x being the score on the fourth test:
Now, solve for x
To find the average of a set of numbers, add up the individual values and divide by the total number of values you have.
For the test scores, we can set up the following equation with x being the score on the fourth test:
Now, solve for x
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Find the mean of the following set of numbers: 
Find the mean of the following set of numbers:
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To find the mean of a set of numbers, you must add them all and then divide their sum by the number of total members of the set.
and there are 
numbers in the set, so we divide 
by 
,
giving us a mean of 
.
To find the mean of a set of numbers, you must add them all and then divide their sum by the number of total members of the set.
giving us a mean of
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In her last 
basketball games, Jo scored 
points, 
points, 
points, 
points, and 
points. How many points per game does she score on average?
In her last
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To find the average, add up all the values you are given and divide by the number of values there are.
18 + 12 + 22 + 24 + 14 = 90, the sum of her total points.
And 90/5 = 18, which is her average.
To find the average, add up all the values you are given and divide by the number of values there are.
18 + 12 + 22 + 24 + 14 = 90, the sum of her total points.
And 90/5 = 18, which is her average.
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Judy received these scores on her last four math tests:
, 
, 
, 
Her teacher calculates the final grade from the mean of five tests, which are all weighted equally. If Judy gets a 
on her fifth test, what will be her overall grade in the class?
Judy received these scores on her last four math tests:
Her teacher calculates the final grade from the mean of five tests, which are all weighted equally. If Judy gets a
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To find Judy's overall grade, you must find the mean of all five test scores.
Add together all five scores:
Then divide the sum by the total number of scores:
is Judy's overall score in the class.
To find Judy's overall grade, you must find the mean of all five test scores.
Add together all five scores:
Then divide the sum by the total number of scores:
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Jimmy's dog had 6 puppies. He weighed the puppies right after they were born. Their weights were 657 grams, 789 grams, 456 grams, 554 grams, 635 grams, and 446 grams. In grams, what was the mean weight of the puppies?
Jimmy's dog had 6 puppies. He weighed the puppies right after they were born. Their weights were 657 grams, 789 grams, 456 grams, 554 grams, 635 grams, and 446 grams. In grams, what was the mean weight of the puppies?
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The mean of a set of numbers is the same as its average.
So then, to find the mean weight for the puppies,
The mean of a set of numbers is the same as its average.
So then, to find the mean weight for the puppies,
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Danielle tracked how much she paid per meal for the past five meals. She paid 
. What was the average she paid per meal?
Danielle tracked how much she paid per meal for the past five meals. She paid
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To find the average (also known as the mean), we use the following formula:
So, for the numbers that are given in the question, we can set up this equation:
To find the average (also known as the mean), we use the following formula:
So, for the numbers that are given in the question, we can set up this equation:
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If the average of 
numbers is 
and the average of 
numbers is 
, what is the average of all the numbers?
If the average of
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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 
.
To find the average of all the numbers, we need to find the sums from each average. Since the average of
The average of
Then, the total sum is
So to find average, we do
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If the average of 
numbers is 
and the average of 
numbers is 
, what was the number added to increase the average?
If the average of
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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
or 
as the final answer.
If the average of
We also know the average of
The expression in the numerator represents the sum. By cross-multiplying, we get
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Find the mean for the following set of numbers:
, 
, 
, 
, and 
Find the mean for the following set of numbers:
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The mean is the same as the average. To find the mean, use the following formula:
The mean is the same as the average. To find the mean, use the following formula:
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Find the mean for the following set of numbers:
, 
, 
, and 
Find the mean for the following set of numbers:
Tap to reveal answer
The mean is the same as the average. To find the mean, use the following formula:
The mean is the same as the average. To find the mean, use the following formula:
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