Welcome to this informative article on the topic ‘What’s 30% of 45? Unlock the Secret to Quick Calculation!’ Are you also struggling with calculations involving percentages? Do you want to know a quick and easy way to find out what is 30% of 45? Well, look no further as we have got you covered. Keep reading to discover the secret behind quick calculations.

In this article, we will discuss what percentage is, how to calculate percentages, and how to calculate what’s 30% of 45. We will also share some tips and tricks to make the calculations faster and easier for you.

## What is Percentage?

Percentage is a way of representing a quantity in terms of another quantity. It is often denoted as a number followed by the symbol %, which means “per cent” or “out of 100.”

For example, if you have a class of 30 students, and 60% of them are girls, it means that 18 students out of 30 are girls.

## How to Calculate Percentages?

Calculating percentages involves finding the ratio of the quantity being represented to the total quantity and multiplying it by 100.

### Formula for Calculating Percentages

**Percentage** = (Quantity being represented/Total Quantity) × 100%

### Example 1:

If you have 20 chocolates, and you want to find out what percentage of the chocolates are dark chocolates, then:

**Quantity being represented**= Number of dark chocolates = 5**Total Quantity**= Total number of chocolates = 20**Percentage**= (5/20) × 100% = 25%

### Example 2:

If 20% of the students in a school are in the first grade, and the school has 500 students, how many students are in the first grade?

**Percentage**= 20% = 0.20 (the % symbol is converted to a decimal)**Total Quantity**= 500 students**Quantity being represented**= (0.20) × 500 = 100 students

## What’s 30% of 45?

Now, let’s come to the main topic of our article. We want to find out what’s 30% of 45. We can use the formula for calculating percentages that we discussed above.

**Percentage**= 30% = 0.30 (the % symbol is converted to a decimal)**Total Quantity**= 45**Quantity being represented**= (0.30) × 45 = 13.5

Therefore, **30% of 45 is 13.5**.

## Tips and Tricks for Quick Calculations

Here are some tips and tricks that can help you make calculations involving percentages faster and easier:

### 1. Use fractions as well as decimals

Some calculations involving percent can be easier to perform by treating the percentage as a fraction. For example, 30% can be represented as 3/10.

### 2. Round off the numbers

If you don’t need an exact answer, rounding off the numbers can make calculations easier. For example, 37% of 138 can be rounded off to 40% of 140, which is easier to calculate mentally.

### 3. Use the percentage change formula

If you want to find out the percentage change between two quantities, you can use the following formula:

**Percentage Change** = ((Final Value – Initial Value)/Initial Value) × 100%

## Conclusion

Percentages are an essential part of mathematics that we use in our everyday lives, from calculating discounts to finding out our performance scores. In this article, we learned what percentage is, how to calculate percentages, and how to calculate what’s 30% of 45. We also shared some tips and tricks for quick calculations.

## Most Common Questions about What’s 30% of 45

Here are some of the most frequently asked questions about this topic:

**Q. What does 30% of 45 mean?****Q. What is 30% off 45?****Q. What is 30% of 45 dollars?****Q. What is the best way to calculate percentages?**

A. 30% of 45 means finding out 30% (or 0.30) of 45 using the formula for calculating percentages.

A. If something costs 45 dollars and is 30% off, you can find out the discount amount by calculating 30% of 45 using the formula for calculating percentages.

A. 30% of 45 dollars is the same as finding out 30% (or 0.30) of 45 using the formula for calculating percentages. The result is 13.5 dollars.

A. The best way to calculate percentages is to use the formula for calculating percentages. You can also use fractions or decimals to make the calculation easier or round off the numbers to avoid complexity.

## References

- “Percentage.” Mathwords. n.d., https://www.mathwords.com/p/percentage.htm.
- “How to Calculate Percentages.” QuickMath. Accessed September 14, 2021. https://www.quickmath.com/handbook/percentage/.