Fraction (mathematics)
A fraction is a number that shows how many equal parts there are. When we write fractions, we show one number with a line above another number, for example, <math>\tfrac{1}{4}</math> or ^{1}⁄_{4} or 1/4. The top number tells us how many parts there are, the second number tells us the total number of parts.
The top part of the fraction is called a numerator. The bottom part of the fraction is called a denominator. For example, <math>\tfrac{1}{4}</math>: The 1 is the numerator here, and the 4 is the denominator.
Examples
- A room where <math>\tfrac{1}{4}</math> of the people are girls, has 1 girl for every 4 people.
- Think of a cake made of 4 equal parts. Each is 1 part of 4. In maths, you write this as <math>\tfrac{1}{4}</math>, and it is called a "quarter". 2 parts of the cake (i.e. 2 quarters) is written <math>\tfrac{2}{4}</math>, and this is also known as 1/2, half.
Mathematical fractions
A fraction is a mathematical expression relating two quantities or numbers, one divided by the other. The numbers may be whole numbers (or integers) – this is a rational number. For example, <math>\tfrac{1}{2}</math> is a fraction. They can also be polynomials – this is a rational function.
Mathematically, a fraction is a quotient of numbers, representing the number's value when the numerator is divided by the denominator (lower number). Thus <math>\tfrac{1}{2}</math> means one divided by two, or, in decimals, 0.5.
To find <math>\tfrac{1}{2}</math> of <math>\tfrac{1}{2}</math>, the denominators are multiplied. That means: denominator 2 multiplied by 2 equals 4 or: <math>\tfrac{1}{2}</math> x <math>\tfrac{1}{2}</math> = <math>\tfrac{1}{4}</math> or: 0.5 x 0.5 = 0.25.
(In this case “<math>\tfrac{1}{2}</math> of” means mathematically "multiplication".)
To find <math>\tfrac{1}{2}</math> divided by <math>\tfrac{1}{2}</math>, multiply <math>\tfrac{1}{2}</math> by the reciprocal of <math>\tfrac{1}{2}</math>, which is 2. That answer is 1.
Multiplying
The numerator is multiplied by the other numerator. The denominator is multiplied by the other denominator. E.g. ^{2}⁄_{4} x ^{3}⁄_{4} = ^{6}⁄_{16} you can simplify this by dividing both the numbers by a common factor.This would be ^{3}⁄_{8}
Other websites
- Curricula for Creating Fractions
- Curricula for Teaching about Fractions
- Teaching Fractions: New Methods, New Resources
- Worksheets:Fractions
- Interactive and dynamic worksheets to visualize fractions
- Worksheets: Identifying Fractions
- Worksheets: Improper Fractions to Mixed Numbers
- Curricula for Teaching about Equivalent Fractions
- Free online quizzes about Fractions
- Endless Examples & Exercises for fractions
- Printable fraction worksheets for elementary grades.