# What percentage of data values fall below the mean?

## What percentage of data values fall below the mean?

In normally distributed data, about 34% of the values lie between the mean and one standard deviation below the mean, and 34% between the mean and one standard deviation above the mean.

## What is the percentage of observation?

The Empirical Rule states that 99.7% of data observed following a normal distribution lies within 3 standard deviations of the mean. Under this rule, 68% of the data falls within one standard deviation, 95% percent within two standard deviations, and 99.7% within three standard deviations from the mean.

How do you find the percent below z score?

Subtract the value you just derived from 100 to calculate the percentage of values in your data set which are below the value you converted to a Z-score. In the example, you would calculate 100 minus 0.22 and conclude that 99.78 percent of students scored below 2,000.

### What percentage of the area falls above the mean?

The percentage of scores will fall above the mean value in a normal curve is 50%.

### What percentage of values fall within this range?

For an approximately normal data set, the values within one standard deviation of the mean account for about 68% of the set; while within two standard deviations account for about 95%; and within three standard deviations account for about 99.7%.

What percent of the data lie 1 standard deviation above the mean?

Empirical Rule or 68-95-99.7% Rule Approximately 68% of the data fall within one standard deviation of the mean.

#### How many observations fall below the median?

It is observed that 3 observations of dataset fall below the mean. Therefore, it is not necessary that half of the observations fall below its mean value.

#### How do you calculate percentage below?

How to Calculate Percentage Decrease

1. Subtract starting value minus final value.
2. Divide that amount by the absolute value of the starting value.
3. Multiply by 100 to get percent decrease.
4. If the percentage is negative, it means there was an increase and not an decrease.

How do you find area above and below z-score?

To find the percentage of the area that lies “above” the z-score, take the total area under a normal curve (which is 1) and subtract the cumulative area to the left of the z-score.

## What percentage of the area falls within 1 standard deviation above and below the mean?

68%
The Empirical Rule or 68-95-99.7% Rule can give us a good starting point. This rule tells us that around 68% of the data will fall within one standard deviation of the mean; around 95% will fall within two standard deviations of the mean; and 99.7% will fall within three standard deviations of the mean.

## What is the percentage of values in the distribution between 17 and 32?

To solve this problem, note that 17-2=15, which is 3 standard deviations. The 68-95-99.7 rule states that 99.7% of the population will lie within 3 standard deviations of the mean; this means in this case that 99.7% lie between 2 and 17+15 = 32.

How many values fall within one standard deviation of the mean?

Approximately 68% of the data values will fall within 1 standard deviation of the mean, from 101 101 to 173 173. Approximately 95% of the data values will fall within 2 standard deviations of the mean, from 65 65 to 209 209.

### How can you find percentages of data away from the mean?

With the Empirical Rule, we can estimate the percentages of data values up to 3 standard deviations away from the mean. The Empirical Rule Calculator above will be able to tell you the percentage of values within 1, 2 or 3 standard deviations of the mean.

### What is the range of z scores within 2 standard deviations?

Within 2 standard deviations – This refers to the range of values between a z-score of -2 to a z-score of +2. And finally, within 3 standard deviations – This refers to the range of values between a z-score of -3 to a z-score of +3.