# The Importance of Equivalence in Mathematics

## 1. Introduction

One of the most complex and challenging ideas that middle school students have to grapple with is that of equivalence. The concept of equivalence is fundamental to much of mathematics, and yet it is often misunderstood or not fully grasped by students. In order to be effective in working with fractions that have unlike denominators, for example, a learner needs to have a good understanding of equivalence.

The concept of equivalence can be difficult to explain, but put simply, it means that two things are equal in value or worth. This is often represented by the equal sign (=), and it means that the two things on either side of the sign are interchangeable. So, if we have the equation 3 + 5 = 8, this means that three plus five is equal to eight, and we can swap around the order of the numbers and still get the same answer. We could also say that three plus five is equivalent to eight.

## 2. The Concept of Equivalence

There are a few different ways in which we can represent equivalence. The most common way is with the equal sign (=), but we can also use the symbol for congruence (≅) or the symbol for equality (≡). These all mean the same thing, but they might be used in different context to make things clearer. For example, we might use ≅ when we are talking about geometric shapes that fit exactly together like puzzle pieces, or we might use ≡ when we are referring to mathematical equations.

It is important to note that when we use any of these symbols, we are saying that the two things on either side are equal in value or worth. This does not necessarily mean that they are identical; it just means that they have the same value. So, if we have two different fractions with unlike denominators, such as ¾ and 6/8, we can say that they are equivalent because they both represent the same amount, even though they look different.

There are a few different ways in which two things can be equivalent. The most common way is by having the same size or value. So, if we have two apples and two oranges, we can say that they are equivalent because each apple has the same value as each orange. We can also say that three apples are equivalent to six oranges because three apples have the same value as six oranges.

Another way in which two things can be equivalent is by having the same quantity. So, if we have two bags of sweets and each bag has 10 sweets in it, then we can say that the two bags are equivalent because they have the same quantity of sweets.

Finally, two things can also be equivalent if they can be interchanged without changing the meaning or outcome of something. So, if we have an equation such as 3 + 5 = 8, then we can say that 3 and 5 are equivalent to 8 because they can be swapped around without changing the outcome of the equation.

## 3. Applying the Concept of Equivalence

The concept of equivalence is extremely important in mathematics because it allows us to solve problems more efficiently. If we can understand that two things are equivalent, then this often makes calculations much easier.

For example, consider the following problem: Emma has 4 sweets and she wants to share them equally with her three friends. How many sweets will each friend get?

If we understand that four sweets is equivalent to 12 sweets (because 4 x 3 = 12), then we can see that each friend will get 3 sweets (because 12 ÷ 3 = 4). This is much easier than working out that 4 ÷ 3 = 1 and then adding this to Emma's original 4 sweets to give each friend 3 sweets.

Similarly, if we want to add two fractions together that have different denominators, such as ¾ and 6/8, then we can understand that these are equivalent to 9/12 and 12/16 because ¾ is equivalent to 9/12 and 6/8 is equivalent to 12/16. This means that we can add the fractions together by adding the numerators and the denominators separately:

9/12 + 12/16 = 9 + 12/16 = 21/16.

This is much easier than working out what ¾ + 6/8 is equal to by converting both fractions to have the same denominator.

## 4. Some Challenging Applications of the Concept of Equivalence

Although the concept of equivalence is relatively simple, there are some challenging applications of it that can be difficult for learners to understand. One such application is when we need to add or subtract fractions that have different denominators. In order to do this, we need to first find an equivalent fraction for one of the fractions so that they have the same denominator. We can then add or subtract the fractions as normal.

For example, consider the following problem: Emma has 3/4 of a pizza and she wants to share it equally with her two friends. How much pizza will each friend get?

We can begin by finding an equivalent fraction for 3/4 so that it has the same denominator as 2/3 (which is the other fraction in the problem). We know that 3 ÷ 4 = 0.75, so we can multiply both the numerator and denominator of 3/4 by 4 to give us 12/16. We can then see that:

3/4 ≅ 12/16 and 2/3 ≅ 8/12.

This means that we can add the fractions together as follows:

12/16 + 8/12 = 20/24.

We can then divide this answer by 2 to give us the answer we are looking for, which is 10/24. This means that each friend will get 10 pieces of pizza out of 24, or just over a quarter of a pizza each.

Another challenging application of equivalence is when we need to divide fractions that have different denominators. In order to do this, we need to first find an equivalent fraction for one of the fractions so that they have the same denominator. We can then divide the fractions as normal.

For example, consider the following problem: Emma has 3/4 of a pizza and she wants to divide it equally between her two friends. How much pizza will each friend get?

We can begin by finding an equivalent fraction for 3/4 so that it has the same denominator as 2/3 (which is the other fraction in the problem). We know that 3 ÷ 4 = 0.75, so we can multiply both the numerator and denominator of 3/4 by 4 to give us 12/16. We can then see that:

3/4 ≅ 12/16 and 2/3 ≅ 8/12.

This means that we can divide the fractions as follows:

12/16 ÷ 8/12 = 12 ÷ 8 = 1.5.

This means that each friend will get 1.5 pieces of pizza, or just over a third of a pizza each.

## 5. Conclusions

In conclusion, the concept of equivalence is extremely important in mathematics, and it is often misunderstood or not fully grasped by students. The effective introduction of equivalence in working with fractions that have unlike denominators depends on the learner's understanding of prior knowledge. Once this understanding has been developed, working with fractions becomes much easier and more efficient.

There are a few different ways in which we can represent equivalence, and it is important to note that when we use any of these symbols, we are saying that the two things on either side are equal in value or worth. Two things can be equivalent if they have the same size or value, the same quantity, or if they can be interchanged without changing the meaning or outcome of something.

The concept of equivalence is extremely important in mathematics because it allows us to solve problems more efficiently. One challenging application of equivalence is when we need to add or subtract fractions that have different denominators. In order to do this, we need to first find an equivalent fraction for one of the fractions so that they have the same denominator. We can then add or subtract the fractions as normal.

Another challenging application of equivalence is when we need to divide fractions that have different denominators. In order to do this, we need to first find an equivalent fraction for one of the fractions so that they have the same denominator. We can then divide the fractions as normal.

In conclusion, the concept of equivalence is extremely important in mathematics, and it is often misunderstood or not fully grasped by students. The effective introduction of equivalence in working with fractions that have unlike denominators depends on the learner's understanding of prior knowledge. Once this understanding has been developed, working with fractions becomes much easier and more efficient.