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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Adding and subtracting fractions

If we want to add two fountain which have the exact same denominator we just add the numerators:      2       1          2 + 1           3       –– + ––   =   –––––   =   ––       5       5              5            5 If we desire to include two fountain which have different denominators, we must very first make them have actually the exact same denominator.We do this by finding the lowest common multiple the the denominators.We contact this the lowest common denominator.For the fractions 2/9 and 5/6 the lowest common denominator is 18.To obtain this we discover the determinants of 6 and also 9. Components of 6 room 1, 2, 3, and 6. Factors of 9 are 1, 3, and also 9. The highest usual factor is 3.6/3 = 2 and also 9/3 = 3.The lowest typical multiple is therefore 3 × 2 × 3 = 18.We climate multiply the top and also bottom the each portion by the aspect which will certainly make the bottom the lowest common denominator:      2       5          2 × 2       5 × 3          4       15          4 + 15         19       –– + ––   =   ––––– + –––––   =   ––– + –––   =   –––––   =   –––       9       6          9 × 2       6 × 3          18     18            18            18 we can also write 19/18 together 1 1/18.To subtract fractions, us do exactly the same other than that us subtract the numerators after recognize the lowest typical denominator:      5       1          5 × 2       1 × 3          10       3          10 – 3         7       –– – ––   =   ––––– – –––––   =   ––– – –––   =   –––––   =   –––       9       6          9 × 2       6 × 3          18     18            18            18

Exercise: including and individually fractions

Add 3/4 and also 2/3 climate subtract 1/6.Check answer to adding and subtracting fountain exercise.Back come Brush up your maths key menu.To boy name Bland"s M.Sc. Index.To young name Bland"s home page.This page maintained by boy name Bland. Critical updated: 26 November, 2007. Back to top.