Basic Statistics - Math

A box and whisker plot separates the data into quartiles so that each quartile has an equal number of data points. The box indicates the interquartile range, that is, the top line of the box is the third quartile and the bottom line of the box is the second quartile. The line separating the second and third quartiles indicates the median. The lines outside of the box indicate the outer-quartiles (first and fourth).

The data points follow an overall linear trend, as opposed to being randomly distributed. Though there are a few outliers, there is a general relationship between the two variables.

A line could accurately predict the trend of the data points, suggesting there is a linear correlation. Since the y-values decrease as the x-values increase, the correlation must be negative. We can see that a line connecting the upper-most and lower-most points would have a negative slope.

An exponential relationship would be curved, rather than straight.

The mean is calculated by adding all the values in a group together, then dividing the sum by the total number in the group. In this case, six homes are for sale. The six home values are added together , then that value is divided by six.

The median is determined by ordering the values in the group from least to greatest: 155, 214, 305, 315, 535, 720. The value directly in the middle is the median. For instance, if there are five numbers, the third is the median. Here, we have an even number of values so there is no value directly in the middle. To find the median when there is no middle-most value, find the average of the two middle values. The mean is determined by adding the two values and dividing by two (the number in the group):

The mean is calculated by adding the values from the four days together, then dividing the sum by the total number of values. In this case, four values must be added:

The mode is the number that appears most frequently in a series of numbers. First, organize the numbers in order from least to greatest: 4, 4, 7, 8, 17, 17, 17, 25, 26, 35. The number 17 appears three times, more than any other number.

Put the data in order from smallest to largest and then calculate each stastic: mean, mode, median, range

or

Mode is the most often repeated number or

Median is the number in the middle or

Mean is the sum of the data divided by the number of data points or

First, convert the weighted percents to decimals.

Next, multiply each score by the weight.

Finally, sum all of the weighted scores.

The first step to finding the median is always to put the numbers in the proper order:

3, 6, 7, 8, 11, 19, 27, 30, 39, 42

When we have an even amount of numbers, we find the average (or mean) of the middle two to get the median:

11 + 19 = 30/2 = 15

In a standard deck of playing cards we have:

So the probability of picking the first card red is .

Then the probability of picking the second card black is because this is without replacement.

They are independent events so the probabilities get multiplied together to give .

First, put the data in order, smallest to largest:

Note, the mode is the number most often repeated in the data set and the median is the middle number.

So is the only true statement.

The mean is calculated by adding all the values in a group, then dividing the sum by the total number in the group.

The mode is the number that appears most frequently in a series of numbers. First, organize the numbers in order from least to greatest. Then, identify the value that is repeated most frequently.

The median is determined by ordering the values in the group from least to greatest and identifying the value directly in the middle. For instance, if five numbers are ordered from least to greatest, the third is the median.

The sample space for rolling two six-sided dice is .

The odd numbers less than seven are one, three, and five.

The smallest sum you can get with two dice is .

sum of

sum of

Probability is a fraction between and that shows how likely something is to happen. The numerator represents target outcomes, and the denominator represents the total outcomes to choose from, or the sample space.

Let the final test score.

The average is given by .

Solve by cross multiplying to get .

Then subtract from both sides to get .

The average is the sum of the data divided by the total number of data points.

Let final score.

Simplify so the equation to solve becomes .

Cross multiplying we get .

Then subtract from both sides and divide by to get .

The range is the simplest measurement of the difference between values in a data set. To find the range, one simply subtracts the lowest value from the greatest value, ignoring the others. Here, the lowest value is 155 and the greatest is 720.