## What is a fraction?

So far we have actually dealt with whole numbers or integers, as uncovered by counting.A fraction is one entirety number divided by another.We compose fractions together one number end another, with a horizontal line in between them, favor this:      3      –      4or in a line of text as one number through a cut or solidus climate the other number, like this: 3/4.The portion 3/4 or three quarters way 3 components out the 4.The top number, 3, is dubbed the numerator and the reduced number, 4, is the denominator.To calculation a portion of something, multiply by the numerator and divide by the denominator.For example, 3/4 of 12 is 9:      3      – × 12 = (3 × 12) ÷ 4 = 36 ÷ 4 = 9       4

### Exercise: fractions

What is a fifty percent as a fraction?What is 4 fifths of 20?Check prize to fractions exercise.

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## Simplifying fractions

Sometime the numerator and denominator have actually a common factor. We deserve to make the portion simpler by dividing top and also bottom through the factor.For example:      15     3 × 5         3      –– = –––––– = ––      20     4 × 5         4because the typical factor that 15 and also 20 is 5. We divide top and bottom by 5.

### Exercise: simple fractions

Simplify 27/30.Check answer to simplifying fractions exercise.

## Improper fractions

Fractions i beg your pardon are in between 0 and also 1 space called ideal fractions.Improper fractions space those higher than 1.For example, 7/4 is an not correct fraction.We can also express this as a totality number and a appropriate fraction: 1¾.

### Exercise: not correct fractions

Express five and two thirds together an not correct fraction.Express       17       ––         5as an integer and also proper fraction.Check answer to improper fractions exercise.

## Reciprocals

The reciprocal of a number is one split by the number.The mutual of 2 is ½.Conversely, the mutual of ½ is 2.To discover the reciprocal of a portion we revolve it over, so that the molecule becomes the denominator and also the denominator becomes the numerator.                                                 4           5 for example, the mutual of   ––   is   ––                                                  5           4 we can convert this to an integer and a proper fraction as 1¼.

### Exercise: reciprocals

What room the the reciprocals that 4 and of 5/6?Check answer to reciprocals exercise.

## Multiplying fractions

To multiply 2 fractions we simply multiply their numerators,multiply their denominators, and also simplify if necessary:      2       1          2 × 1           2           1       –– × ––   =   –––––   =   ––   =   ––       3       2          3 × 2          6          3

### Exercise: multiply fractions

Multiply four fifths by 3 quarters.Check answer come multiplying fountain exercise.

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