you need
  • - mathematics textbook for the fifth grade.
Guide
1
So, let's look at the definition of parts of the whole.To do this, drawing a rectangle or square, the best on a sheet in the box.Divide the square on the cell, it will share equal parts of a whole.

Fractions are different, for example, common - 1/2, 3/7, 1/4, mixed - 1 ½, 2 ½

5 ¼, decimals - 0.25, 0.5, 0.7.
2
All fractions depends on the basic properties of the fractions - fractions will not change if the numerator and denominator of the increase or decrease on the same number.Follow this rule, use the task of reducing fractions, solve the problem without a calculator.
3
Fractions can be converted from one form to another.For example, the fraction can be written as 25/100 0.25.A fraction can be reduced, turn ¼.It happens that the decimal is not necessary to cut.For example, 0.3 will remain 3/10 - this fraction is not reduced.But beware, not all ordinary fractions can be represented in decimal form.Do not find a decimal fraction of 1/3, 6/7, 1/7, and there are not a lot of translated fractions.
4
Try to find a decimal fraction of 3/20.To begin lay the denominator of this fraction into simple factors, such as 5 * 2 * 2.Record as an example: 3/20 = 3/20 * 5/5 = 15/100 = 0.15.

So, to find a decimal fraction, the denominator lay common fraction factorization, call the number of fives and deuces, select a single factor.Secure knowledge - get the decimal fraction of 3/50.Arrange the denominator factorization 50 = 2 * 5 * 5, then you need to submit a deuce in a fraction 2/2.3/50 * 2/2 = 6/100 = 0.06.
5
To find a decimal fraction of an ordinary share of its numerator by the denominator.For example, take the 5/8, Section 5 to 8, will get 0,625.Decimal can be infinite.For example, 18/7 in the exact decimal turn is impossible, because if 18 will be divided into an infinite number seven.