Normal Distribution CDF for 2 Tails Calculator
Calculates the 2 tail cumulative normal distribution function.
The 2 tail cumulative normal distribution function.
Formula: 1 - (1 - normdist(x, mn, sd, 1)) * 2
See the Statistical Distributions Overview page for more statistical distribution calculators.
Example 1
A baseball shall weigh not less than five nor more than 5 1/4 ounces avoirdupois.
If a shipment has an mn of 5 1/8 oz and sd of .1 oz, what percent are within the specifications
| Value | Keystrokes | Display | Description |
|---|---|---|---|
| 5.25 | x | 5.2500 | Stores the x value. |
| 5.125 | μ | 5.1250 | Stores the mn (mean) value. |
| .1 | σ | 0.1000 | Stores the sd (standard deviation) value. |
| cdf | 0.7887 | Calculates the cumulative distribution between -x and +x. |
So, about 75%
Example 2
What should the standard deviation of be so that 99% are within the specifications?
These keystrokes assume the values from example 1.
| Value | Keystrokes | Display | Description |
|---|---|---|---|
| .99 | cdf | .9900 | Stores the cdf value. |
| σ | 0.0485 | Calculates the sd value. |
Reference: