Fractions

Fractions are an important concept in mathematics that students typically start learning in elementary school. Here’s a brief introduction to fractions with some examples:

A fraction represents a part of a whole. The whole can be a number, a shape, or anything else that can be divided into equal parts. A fraction has two parts: the top number is called the numerator, and the bottom number is called the denominator. The numerator represents the number of equal parts you have, while the denominator represents the total number of equal parts that make up the whole.

For example, if you have a pizza cut into 8 equal slices, and you have eaten 3 of those slices, you can represent the part of the pizza you have eaten as the fraction 3/8. In this case, 3 is the numerator (the number of slices you have eaten) and 8 is the denominator (the total number of slices).

Here are some more examples:

If you have a rectangle that is divided into 4 equal parts, and you have shaded in 2 of those parts, you can represent the shaded part as the fraction 2/4. However, we can simplify this fraction by dividing both the numerator and denominator by 2 to get 1/2, which represents the same shaded part.
If you have a bag with 12 marbles, and 5 of those marbles are blue, you can represent the part of the marbles that are blue as the fraction 5/12.
If you have a number line that goes from 0 to 1, and you divide it into 4 equal parts, the distance between 0 and 1/4 is one quarter of the whole distance. Similarly, the distance between 1/4 and 1/2 is also one quarter of the whole distance, and so on.

Add Fractions

Adding fractions can seem daunting at first, but it’s actually quite simple once you understand the process. Here are the steps to follow:

Step 1: Find a common denominator To add two fractions with different denominators, you need to find a common denominator. The common denominator is the least common multiple of the denominators. For example, if you want to add 1/3 and 2/5, you need to find the least common multiple of 3 and 5, which is 15.

Step 2: Rewrite the fractions with the common denominator Once you have found a common denominator, rewrite both fractions using that denominator. To do this, you multiply the numerator and denominator of each fraction by the same number that will result in the common denominator. For example, to rewrite 1/3 with a denominator of 15, you would multiply both the numerator and denominator by 5 to get 5/15. To rewrite 2/5 with a denominator of 15, you would multiply both the numerator and denominator by 3 to get 6/15.

Step 3: Add the numerators Once you have both fractions with the same denominator, you can add the numerators. Simply add the numerators of the two fractions, and keep the denominator the same. For example, adding 5/15 and 6/15 gives you 11/15.

Step 4: Simplify the fraction (if necessary) If the resulting fraction is not already in its simplest form, simplify it by dividing both the numerator and denominator by their greatest common factor. For example, 11/15 can be simplified by dividing both the numerator and denominator by 1, which gives you 11/15 in its simplest form.

Here’s an example to illustrate the process:

1/3 + 2/5

Step 1: The least common multiple of 3 and 5 is 15.

Step 2: Rewriting the fractions with a denominator of 15: 1/3 = 5/15 (multiply numerator and denominator by 5) 2/5 = 6/15 (multiply numerator and denominator by 3)

Step 3: Adding the numerators: 5/15 + 6/15 = 11/15

Step 4: The fraction is already in its simplest form, so we’re done!

So, 1/3 + 2/5 = 11/15.

Find the Least Common Denominator between Fractions and Why?

To add or subtract fractions, you often need to find a common denominator. Here are the steps to find a common denominator between two fractions:

Step 1: Identify the denominators Look at the two fractions you want to add or subtract and identify their denominators. For example, if you want to add 1/3 and 1/4, the denominators are 3 and 4.

Step 2: Find the least common multiple (LCM) Find the least common multiple (LCM) of the denominators. The LCM is the smallest number that is a multiple of both denominators. There are several methods to find the LCM, but one common method is to list the multiples of each denominator and find the smallest one that appears in both lists. For example, the multiples of 3 are: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, … and the multiples of 4 are: 4, 8, 12, 16, 20, 24, 28, 32, … The smallest multiple that appears in both lists is 12, so the LCM of 3 and 4 is 12.

Step 3: Rewrite the fractions with the common denominator Rewrite each fraction with the common denominator found in step 2. To do this, multiply the numerator and denominator of each fraction by the same factor so that the denominator becomes the LCM. For example, to rewrite 1/3 with a denominator of 12, you would multiply both the numerator and denominator by 4 to get 4/12. To rewrite 1/4 with a denominator of 12, you would multiply both the numerator and denominator by 3 to get 3/12.

Step 4: Add or subtract the fractions Now that the fractions have a common denominator, you can add or subtract them by simply adding or subtracting the numerators, and keeping the denominator the same. For example, to add 1/3 and 1/4, you would rewrite the fractions with a common denominator of 12, which gives you 4/12 and 3/12. Then, you can add the numerators to get 7/12.

Step 5: Simplify the result (if necessary) If the result is not already in its simplest form, simplify it by dividing the numerator and denominator by their greatest common factor. For example, if the result is 7/12, you can simplify it by dividing both the numerator and denominator by 1, which gives you 7/12 in its simplest form.

How to Multiply Fractions

Multiplying fractions is a straightforward process. Here are the steps:

Step 1: Multiply the numerators To multiply two fractions, simply multiply the numerators together. For example, if you want to multiply 2/3 and 1/4, you would multiply 2 and 1 to get 2.

Step 2: Multiply the denominators Next, multiply the denominators together. For example, to multiply 2/3 and 1/4, you would multiply 3 and 4 to get 12.

Step 3: Write the result as a fraction The product of the two fractions is the result of the multiplication. Write this result as a fraction, with the numerator being the product of the two numerators, and the denominator being the product of the two denominators. For example, the product of 2/3 and 1/4 is 2/12.

Step 4: Simplify the result (if necessary) If the resulting fraction is not already in its simplest form, simplify it by dividing both the numerator and denominator by their greatest common factor. For example, if the result is 2/12, you can simplify it by dividing both the numerator and denominator by 2, which gives you 1/6 in its simplest form.

Here’s an example to illustrate the process:

2/3 x 1/4

Step 1: Multiply the numerators: 2 x 1 = 2

Step 2: Multiply the denominators: 3 x 4 = 12

Step 3: Write the result as a fraction: 2/12

Step 4: Simplify the result: 2/12 can be simplified by dividing both the numerator and denominator by 2, which gives 1/6.

So, 2/3 x 1/4 = 1/6.

How to Divide Fractions

Dividing fractions is a bit more complicated than multiplying, but it is still a fairly simple process. Here are the steps:

Step 1: Flip the second fraction To divide two fractions, you need to multiply the first fraction by the reciprocal of the second fraction. To find the reciprocal of a fraction, simply flip it upside down (i.e., swap the numerator and denominator). For example, if you want to divide 2/3 by 1/4, you would flip 1/4 to get 4/1.

Step 2: Multiply the fractions Once you have flipped the second fraction, you can multiply the two fractions together. For example, to divide 2/3 by 1/4, you would multiply 2/3 by 4/1, which gives you (2/3) x (4/1) = 8/3.

Step 3: Simplify the result (if necessary) If the resulting fraction is not already in its simplest form, simplify it by dividing both the numerator and denominator by their greatest common factor. For example, if the result is 8/3, you can simplify it by dividing both the numerator and denominator by 1, which gives you 8/3 in its simplest form, or 2 2/3 as a mixed number.

Here’s an example to illustrate the process:

2/3 ÷ 1/4

Step 1: Flip the second fraction: 1/4 becomes 4/1

Step 2: Multiply the fractions: (2/3) x (4/1) = 8/3

Step 3: Simplify the result: 8/3 is already in its simplest form

So, 2/3 ÷ 1/4 = 8/3 or 2 2/3.

Note that if the second fraction is an integer (i.e., a whole number), you can convert it to a fraction with a denominator of 1 before flipping it. For example, to divide 2/3 by 2, you would convert 2 to the fraction 2/1, flip it to get 1/2, and then multiply 2/3 by 1/2 to get 1/3.