GMAT Math : GMAT Quantitative Reasoning
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Example Questions
Example Question #474 : Arithmetic
Sandra's grade in economics depends on seven tests - five hourly tests, a midterm, and a final exam. The midterm counts twice as much as an hourly test; the final, three times as much.
Sandra's grades on the five hourly tests are 84, 86, 76, 89, and 93; her grade on the midterm was 72. What score out of 100 must she achieve on the final exam so that her average score at the end of the term is at least 80?
She cannot achieve this average this term
This is a weighted mean, with the hourly tests assigned a weight of 1, the midterm assigned a weight of 2, and the final assigned a weight of 3. The total of the weights will be
If we let 
For Sandra to get a final average of 80, then we set the above equal to 80 and calculate 
Example Question #475 : Arithmetic
Consider the following set of numbers:
85, 87, 87, 82, 89
What is the mean?
Example Question #2031 : Gmat Quantitative Reasoning
Consider the following set of numbers:
85, 87, 87, 82, 89
What is the median?
Reorder the values in numerical order:82, 85, 87, 87, 89
The median is the center number, 87.
Example Question #2032 : Gmat Quantitative Reasoning
Find the mean of the sample data set.
The mean of a sample data set is the sum of all of the values divided by the total number of values. In this case:
Example Question #2034 : Problem Solving Questions
The average of the following 6 digits is 75. What is a possible value of 
80, 78, 78, 70, 71,
Therefore, the sum of all 6 digits must equal 450.
Subtract 377 from both sides.
Example Question #2033 : Gmat Quantitative Reasoning
When assigning a score for the term, a professor takes the mean of all of a student's test scores except for his or her lowest score.
On the first five exams, Donna has achieved the following scores: 76, 84, 80, 65, 91. There is one more exam in the course. Assuming that 100 is the maximum possible score, what is the range of possible final averages she can achieve (nearest tenth, if applicable)?
Minimum 79.2; maximum 86.2
Minimum 80, maximum 84
Minimum 66; maximum 71.8
Minimum 79.2; maximum 99.2
Minimum 66; maximum 99.2
Minimum 79.2; maximum 86.2
The worst-case scenario is that she will score 65 or less, in which case her score will be the mean of the scores she has already achieved.
The best-case scenario is that she will score 100, in which case the 65 will be dropped and her score will be the mean of the other five scores.
Example Question #14 : Calculating Arithmetic Mean
What is the mean of this data set?
Add the numbers and divide by 6:
Example Question #2032 : Problem Solving Questions
If 
Insufficient information is given to answer this question.
The mean of 
If you add both sides of each equation:
or
Equivalently,
making 290 the mean.
Example Question #2037 : Problem Solving Questions
What is the mean of the following data set in terms of 
Add the expressions and divide by the number of terms, 8.
The sum of the expressions is:
Divide this by 8:
Example Question #15 : Calculating Arithmetic Mean
Julie's grade in a psychology class depends on three tests, each of which are equally weighted; one term paper, which counts half as much as a test; one midterm, which counts for one and one-half as much as a test; and one final, which counts for twice as much as the other tests.
Julie has scored 85%, 84%, and 74% on her three tests, 90% on her term paper, and 72% on her midterm. She is going for an 80% in the course; what is the minimum percent she must score on the final (assuming that 100% is the maximum possible) to achieve this average?
She cannot achieve this average this term.
Let 
Simplify and solve for 
Julie must make a minimum of 82% on the final to meet her goal.
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