Solving Mathematical Expressions: A Guide to 18 x 3 - 20 ÷ 5

Introduction

Mathematical expressions can sometimes be confusing, especially when dealing with operations like multiplication, division, addition, and subtraction. This article will guide you through the process of solving the expression 18 x 3 - 20 ÷ 5 using the correct order of operations. By understanding this method, you can simplify complex equations and solve them accurately.

Understanding the BODMAS and DMAS Rules

The order of operations can be remembered using the acronyms BODMAS (Brackets, Orders, Division, Multiplication, Addition, Subtraction) and DMAS (Division, Multiplication, Addition, Subtraction). Both acronyms essentially guide you to perform operations in a specific order to ensure the correct result.

BODMAS Rule

1. **Brackets**: Solve anything inside brackets first. In this case, there are no brackets.

2. **Orders**: Evaluate powers and roots. Again, in this expression, there are no orders.

3. **Division and Multiplication**: Perform these operations from left to right.

4. **Addition and Subtraction**: Finally, perform these from left to right.

DMAS Rule

1. **Division**: Divide first, then move to other operations.

2. **Multiplication**: Next, perform the multiplication.

3. **Addition and Subtraction**: Lastly, perform these operations from left to right.

Solving 18 x 3 - 20 ÷ 5 Using BODMAS

Let's break down the expression 18 x 3 - 20 ÷ 5 step by step using the BODMAS rule:

1. **Division**: 20 ÷ 5 4

2. **Multiplication**: 18 x 3 54

3. **Subtraction**: 54 - 4 50

Therefore, the expression 18 x 3 - 20 ÷ 5 simplifies to 50.

Solving 18 x 3 - 20 ÷ 5 Using DMAS

Now let's solve it using the DMAS rule:

1. **Division**: 20 ÷ 5 4

2. **Multiplication**: 18 x 3 54

3. **Subtraction**: 54 - 4 50

The result is the same using both rules: 50.

Conclusion

Solving the expression 18 x 3 - 20 ÷ 5 requires a clear understanding of the order of operations, specifically BODMAS or DMAS. By following these rules, you can ensure that you solve the expression accurately and efficiently. Whether you are a student, a teacher, or anyone else who works with mathematical expressions, understanding and applying the correct order of operations is crucial.

Related Resources

For more detailed explanations and practice, you can download the Eduthrill app. This app is excellent for improving speed and understanding in solving such questions. Additionally, you can refer to the book Algebra with Trigonometry for College Students Third Edition by Jerome E. Kaufmann for deeper insights into algebraic expressions.