To find the median, arrange the numbers from smallest to largest:

 4,4,4,4,6,7,9,9,12,12,12,12,12,12,18,76,90

There are 17 numbers in total.  Since 17 is an odd number, the median will be the middle number of the set.  In this case, it is the 9th number, which is 12.

Treat the percentages as a list, as we are including every demographic from the 3 vehicle types mentioned. If we do each 0.06(5000), 0.12(5000), and 0.15(5000) we note from observation that the median, or middle value, would have to be the 12% row since the sample size does not change. The question asks for EITHER of the 3 categories, so we can ignore the other two.

0.12(5000) = 600 (van) is the median of the 3 categories.

Begin by ordering the set from smallest to largest:

Already, we see that the mode is 8. Find the median by taking the average of the two middle numbers:

Find the mean by adding all numbers and dividing by the total number of terms:

Of the three, the mean of the set is the largest.

To solve this problem, we must be aware of the definition of a median for a set of numbers. The median is defined as the number that is in middle of a set of numbers sorted from smallest to largest. Therefore we must first sort the numbers from largest to smallest.

34,43,45,50,56,65,70,76,76,82,87,88,92,95,100

43,45,50,56,65,70,76,76,81,87,88,82,95

45,50,56,65,70,76,76,81,87,88,82

50,56,65,70,76,76,81,87,88

56,65,70,76,76,81,87

65,70,76,76,81

70,76,76

76

Then by slowly eliminating the smallest and the largest numbers we find that the median score for this test is 76.

Begin by reordering the set in numerical order:

Then becomes

Since there is an odd number of values, the median is the middle value.

Quantity B: 

Now, to find the arithmetic mean, take the sum of values divided by the total number of values.

Quantity A: 

 is an unknown value, but it can be found given what we know about the mean of the set :

Now,  is out of order; arrange in numerically:

Since there are even number of values, the median is the mean of the two middle most values:

The arithmetic mean is the average of the sum of a set of numbers divided by the total number of numbers in the set. This is not to be confused with median or mode.

In Column A, the mean of 5.66 is obtained when the sum (17) is divided by the number of values in the set (3).

In Column B, the mean of 7 is obtained when 21 is divided by 3. Because 7 is greater than 5.66, Column B is greater. The answer is Column B.

Rate = distance/time.

Find the distance for each individual segment of the run (4 miles and 3.25miles). Then add total distance and divide by total time to get the average rate, while making sure the units are compatible (miles per hour not miles per minute), which means the total 45 minute run time needs to be converted to 0.75 of an hour; therefore (4miles + 3.25 miles/0.75 hour) is the final answer.

Note that:

The arithmetic mean of the 100 data points encompassing A and B = 

(total data of Sample Set A + total data of Sample Set B)/100

We have Mean of Sample Set A = 50, or:

(total of Sample Set A) / 25 = 50

And we have Mean of Sample Set B = 100, or:

We can calculate the arithmetic mean by adding up the numbers in a set, and dividing that total by the count of numbers in the set.

Thus, we know that (x + y + z) / 3 = 15. (Multiply both sides by 3.)

x + y + z = 45

We add w = 10 to that, and divide by the new count, 4.

55 / 4 = 13.75