Utilizing the “What is X Percent of Y Calculator”,** we can compute that 18% of 30 equals 5.4**.

**Tips: Directly enter the numerical values. The calculator will automatically calculate the result.**

Table of Contents

## Step-by-Step Solution: What is 18% of 30?

Now that we know we want to find 18% of 30, let’s look at **two different step-by-step methods** we can use to solve this percentage problem. Each approach arrives at the same solution, **but understanding different ways to think through the math builds flexibility and deeper learning**.

### Method 1: Convert the Percent to a Decimal and Multiply

One approach to finding 18 percent of 30 is to convert the percent to a decimal and multiply. Here are the steps:

#### Step 1: Identify the **part** and** whole**

The part is the amount we want as a percentage. In this case, it is **18%**.

The whole is the total amount. In this case, the whole is **30**.

#### Step 2: Write the percentage as a decimal by dividing it by 100:

**18% = 18100 = 0.18**

#### Step 3: Multiply the decimal form of percentage by the whole amount:

**0.18 * 30 = 5.4**

**Therefore, 18% of 30 is 5.4.**

#### Let’s look at this visually:

**18% * 30 = 18100 * 30 = 0.18 *30 = 5.4**

This approach of converting the percentage to a decimal and multiplying is straightforward and can be applied to any “percent of number” problem. The key is properly converting the percent to a decimal by dividing by 100.

### Method 2: Finding Percentages Using Algebraic Equations

Another way to find 18% of 30 is to set up an algebraic equation and solve it. Here are the steps:

A **proportion** is an equation that states two ratios are equivalent. Here is the proportion formula:

**PartWhole = Percentage100**

#### Step 1: Define the Unknown Variable

Let’s define an unknown variable **x** to represent 18% of 30. In algebraic equations, variables are used to represent unknown values.

#### Step 2: Set Up the Equation

Using the variable **x**, we can set up an equation with the information given:

- The unknown variable x (
**Part**) is the amount we want to find, which is 18% of 30 - The
**Whole**is**30** - The
**Percentage**is**18**

**Substitute into the equation:**

In this case, we can multiply both sides of the equation by 30

**30 *x30 = 18100 * 30**

**x = 18 100 * 30 = 540100 = 5.4**

Therefore, 18% of 30 is 5.4.

### Comparing the Methods

Both methods arrive at the same solution:

- Method 1 gets the solution by converting 18% to 0.18 and multiplying by 30.
- Method 2 sets up an equation, defines a variable, and solves algebraically.

The decimal conversion method is straightforward, avoiding any algebra. But the algebraic method is more flexible for complex problems where defining variables and setting up equations is helpful.

**Common Percentage Scenarios**

Here are some common percentage scenarios and how to solve them:

## Finding the Percentage Given the Part and Whole

Here is the proportion formula:

**PartWhole = Percentage100**

We will now demonstrate how to utilize proportion formula to calculate the percentage given a part and whole amount through an example determining what percent of 30 is 5.4.

### What Percent of 30 is 5.4?

#### Step 1: Define the Unknown Variable

Let unknown variable** x** = the unknown percent we want to find..

#### Step 2: Set Up the Equation

Using the variable **x**, we can set up an equation with the information given:.

- The unknown variable
**x**(**Percentage**) is the number we want to find. - The
**Part**is**5.4** - The
**Whole**is**30**

**Substitute into the equation:**

**5.430 = x100**

#### Step 3: Solve the Equation

To isolate x, we can cross multiply as follows:

- Take the numerator of one side of the equation, which is
**5.4** - Multiply it by the denominator of the other side of the equation, which is
**100** - Set that equal to the numerator of the second half (
**x**) multiplied by the denominator of the first half (**30**)

When written out, the cross multiplication looks like:

**5.4 * 100 = x * 30**

**x * 30 = 5.4 * 100**

Then we can solve the resulting equation:

**x * 30 = 540**

**x = 18**

**Therefore, the answer is that 18% of 30 is 5.4.**

## Finding the Whole Given the Percentage and Part

Here is the proportion formula:

**PartWhole = Percentage100**

We will now demonstrate how to utilize proportion formula to calculate the whole given the percentage and part through an example determining 5.4 is 18 Percent of What Number.

### 5.4 is 18 Percent of What Number?

#### Step 1: Define the Unknown Variable

Let unknown variable** x** = the unknown number we want to find.

#### Step 2: Set Up the Equation

Using the variable **x**, we can set up an equation with the information given:

- The unknown variable
**x**(**Whole**) is the number we want to find. - The
**Part**is**5.4** - The
**Percentage**is**18**

**Substitute into the equation:**

**5.4x = 18100**

#### Step 3: Solve the Equation

To isolate x, we can cross multiply as follows:

- Take the numerator of one side of the equation, which is
**5.4** - Multiply it by the denominator of the other side of the equation, which is
**100** - Set that equal to the numerator of the second half (
**18**) multiplied by the denominator of the first half (**x**)

When written out, the cross multiplication looks like:

**5.4 * 100 = 18 * x**

**x * 18 = 5.4 * 100**

Then we can solve the resulting equation:

**x * 18 = 540**

**x = 30**

**Therefore, the answer is that 5.4 is 18% of 30.**

## Common Percentage Calculations

Here is a quick reference table of some typical percentage calculations:

Calculation | Formula | Example |
---|---|---|

Find what percentage a part is of a whole | Part / Whole x 100% | 5.4 / 30 x 100% = 18% |

Find what percentage a part is of a whole | Part / Percentage | 5.4 / 18% = 30 |

Find the part given the whole and percentage | Whole x Percentage | 30 * 18% =5.4 |

Having these common formulas memorized can make solving a variety of percentage problems quicker. When in doubt, break things down step-by-step into smaller pieces.

## Standard Percentage of 30 Calculation Examples

**5 Percent of 30 = 5100 * 30 = 0.05 * 30 = 1.5**

**10 Percent of 30 = 10100 * 30 = 0.1 * 30 = 3**

**15 Percent of 30 = 15100 * 30 = 0.15 * 30 = 4.5**

**20 Percent of 30 = 20100 * 30 = 0.2 * 30 = 6**

**25 Percent of 30 = 25100 * 30 = 0.25 * 30 = 7.5**

**30 Percent of 30 = 30100 * 30 = 0.3 * 30 = 9**

**35 Percent of 30 = 35100 * 30 = 0.35 * 30 = 10.5**

**40 Percent of 30 = 40100 * 30 = 0.4 * 30 = 12**

**45 Percent of 30 = 45100 * 30 = 0.45 * 30 = 13.5**

**50 Percent of 30 = 50100 * 30 = 0.5 * 30 = 15**

**55 Percent of 30 = 55100 * 30 = 0.55 * 30 = 16.5**

**60 Percent of 30 = 60100 * 30 = 0.6 * 30 = 18**

**65 Percent of 30 = 65100 * 30 = 0.65 * 30 = 19.5**

**70 Percent of 30 = 70100 * 30 = 0.7 * 30 = 21**

**75 Percent of 30 = 75100 * 30 = 0.75 * 30 = 22.5**

**80 Percent of 30 = 80100 * 30 = 0.8 * 30 = 24**

**85 Percent of 30 = 85100 * 30 = 0.85 * 5.4 = 25.5**

**90 Percent of 30 = 90100 * 30 = 0.9 * 30 = 27**

**95 Percent of 30 = 95100 * 30 = 0.95 * 30 = 28.5**

**100 Percent of 30 = 100100 * 30 = 1 * 30 = 30**