Combination Calculator

Welcome to the Combination Calculator. This tool allows you to calculate the number of combinations for a given set of items. A combination is a collection of objects in any sequence. This is often used in probability and statistics.

\( \mathrm{ \mbox{nCk} = \frac{n!}{k! \times (n-k)!} } \)


Result :


How to Use the Combination Calculator

  1. Enter the Value of n (Total Number of Items)

    Locate the input field labeled "Enter n value." Enter the total number of items or elements in this field. This is the number from which you are selecting items.

  2. Enter the Value of r (Number of Items to Select)

    Locate the input field labeled "Enter k value." Enter the number of items you want to select from the total number of items.

  3. Calculate the Combination

    After entering the values for n and k, click the "Calculate" button. The calculator will process the input and display the result, showing the number of combinations possible.

  4. Review the Detailed Solution

    The calculator will provide a step-by-step solution using the combination formula \( \mathrm{ \mbox{nCk} = \frac{n!}{r!(n-k)!} } \). Review the detailed steps to understand how the result was computed.

Combination Formula

The combination formula is used to determine the number of possible selections in a set when the order of the elements does not matter. The formula is given by:

\( \mathrm{ \mbox{nCr} = \frac{n!}{r!(n-r)!} } \)

Where:

This formula calculates the number of ways to choose r items from n items without considering the order of selection.

How to Calculate Combinations Manually

To calculate combinations manually, follow these steps:

  1. Step 1: Write down the combination formula: \( \mathrm{ \mbox{nCr} = \frac{n!}{r!(n-r)!} } \).
  2. Step 2: Calculate the factorial of n, which is the product of all positive integers up to n.
  3. Step 3: Calculate the factorial of r and the factorial of (n - r).
  4. Step 4: Substitute the factorial values into the formula.
  5. Step 5: Simplify the expression to find the number of combinations.

Example: To calculate \( \mathrm{ \mbox{15C10} } \):