# CRITBINOM

The `CRITBINOM` function calculates the smallest value of x for which the cumulative binomial distribution is less than a specified value. This function is commonly used in statistical analysis to find the minimum number of successes required in a certain number of trials to achieve a desired level of confidence.

## Usage

Use the `CRITBINOM` formula with the syntax shown below, it has 3 required parameters:

Parameters:
1. num_trials (required):
The number of trials in the binomial distribution. Must be a positive integer.
2. prob_success (required):
The probability of success for each trial. Must be between 0 and 1, inclusive.
3. target_prob (required):
The desired cumulative probability for x. Must be between 0 and 1, inclusive.

## Examples

Here are a few example use cases that explain how to use the `CRITBINOM` formula in Google Sheets.

### Calculate the minimum number of successes required in a certain number of trials

Suppose you want to know how many successful sales calls you need to make out of 20 total calls in order to have a 90% chance of closing at least one sale. You can use `CRITBINOM` to find the minimum number of successes required.

### Determine the probability of achieving a certain number of successes

If you know the number of trials and the probability of success for each trial, you can use `CRITBINOM` to find the probability of achieving a specific number of successes.

### Calculate the risk of a certain outcome

Suppose you are a doctor and you want to know how many patients you need to treat with a certain drug in order to have a 95% chance of seeing at least one negative side effect. You can use `CRITBINOM` to find the minimum number of patients required.

## Common Mistakes

`CRITBINOM` not working? Here are some common mistakes people make when using the `CRITBINOM` Google Sheets Formula:

### Incorrect order of arguments

Make sure to input the arguments in the correct order: num_trials, prob_success, target_prob.

### Non-numeric input

Ensure that all input values are numeric and do not contain any non-numeric characters or extra spaces.

### Invalid range

Ensure that the input values for num_trials, prob_success, and target_prob are within a valid range.

### Target probability too high or low

The target probability must be between 0 and 1. Check that you have inputted a value within this range.

### Wrong formula for task

Double-check that CRITBINOM is the correct formula for the task you are trying to accomplish. There may be a different formula that better fits your needs.

The following functions are similar to `CRITBINOM` or are often used with it in a formula:

• `BINOMDIST`

The `BINOMDIST` function calculates the probability of a certain number of successes in a fixed number of trials given a constant probability of success for each trial. This function is commonly used in statistical analysis and hypothesis testing.

• `NEGBINOMDIST`

The `NEGBINOMDIST` function calculates the probability of having a certain number of failures (`num_failures`) before a certain number of successful outcomes (`num_successes`) occur, given the probability of success in a single trial (`prob_success`). This function is often used in statistical analysis to model the number of failures before a certain number of successes in a sequence of independent and identically distributed Bernoulli trials.

You can learn more about the `CRITBINOM` Google Sheets function on Google Support.