# Rule of Three Calculator

#### Usage Instructions:

**Objective:** Calculate the unknown value X based on the Rule of Three, where Value A corresponds to Value B, and Value C corresponds to X.

**Steps:**

**Enter Value A:**Input the first known value (A).**Enter Value B:**Input the second known value (B) that corresponds to A.**Enter Value C:**Input the known value (C) that corresponds to X.**Click the "Calculate X" Button:**After entering all values, click the**"Calculate X"**button to get the unknown value X.**View the Result:**The calculated value X will be displayed in the results section.

The Rule of Three is a mathematical principle used to solve problems involving proportions. It helps find an unknown value when three values are known and they are in a proportional relationship. Here’s a detailed guide on how to use the Rule of Three:

**What is the Rule of Three?**

The Rule of Three is based on the concept of direct or inverse proportionality. If three quantities are known, you can find the fourth quantity if the quantities are proportional.

**Types of Proportionality:**

**Direct Proportionality:**- When two quantities increase or decrease together.
**Example:**If 5 apples cost $10, how much would 8 apples cost?

**Inverse Proportionality:**- When one quantity increases as the other decreases.
**Example:**If 4 workers can complete a task in 6 days, how many days will it take 6 workers to complete the same task?

**How to Use the Rule of Three**

**1. Direct Proportionality**

**Formula:**- (Value 1 / Value 2) = (Value 3 / Value 4)

**Steps:**- Set up the proportion using the known values.
- Cross-multiply to solve for the unknown value.

**Example Calculation:****Problem:**If 5 apples cost $10, how much do 8 apples cost?**Setup:**- 5 apples / $10 = 8 apples / X dollars

**Solve:**- (5 × X) = (8 × 10)
- 5X = 80
- X = 16

**Answer:**8 apples cost $16.

**2. Inverse Proportionality**

**Formula:**- (Value 1 × Value 2) = (Value 3 × Value 4)

**Steps:**- Set up the inverse proportion using the known values.
- Solve for the unknown value.

**Example Calculation:****Problem:**If 4 workers can complete a task in 6 days, how many days will it take 6 workers?**Setup:**- 4 workers × 6 days = 6 workers × X days

**Solve:**- 24 = 6X
- X = 4

**Answer:**It will take 6 workers 4 days to complete the task.

**Quick Reference Table**

Here’s a table showing how the Rule of Three applies to different scenarios:

Known Values |
Unknown Value Calculation |
Example Result |
---|---|---|

5 apples, $10 | 8 apples / X dollars | $16 |

4 workers, 6 days | 6 workers / X days | 4 days |

10 liters, $30 | 15 liters / X dollars | $45 |

2 machines, 5 hours | 3 machines / X hours | 3.33 hours |

**Why Use the Rule of Three?**

**Problem Solving:**Quickly solves problems involving proportions in various fields such as finance, engineering, and everyday tasks.**Practical Applications:**Useful for budgeting, scaling recipes, adjusting project timelines, and more.

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