In the 5th class of high school the concept of fraction is entered. The fraction is the number consisting of the whole quantity of shares of units. Common fractions register in a look ±m/n, call number m fraction numerator, number n – its denominator. If the module of a denominator is more than numerator module, for example 3/4, then the fraction is called proper, otherwise – wrong. The fraction may contain the whole part, for example 5 * (2/3). It is possible to apply various arithmetic operations to fractions.
Instruction
1. Reduction to a common denominator. Let fractions of a/b and with / be given to d. - First of all there is a number of NOC (least common multiple) for denominators of fractions. - The numerator and a denominator of the first fraction is multiplied by NOC/b-Numerator and the denominator of the second fraction is multiplied by NOC/dÅÓ¿¼ÑÓ is given in the drawing. For comparison of fractions they need to be reduced to a common denominator, then to compare numerators. For example, 3/4 <4/5, see the drawing.
2. Addition and subtraction of fractions. For finding of the sum of two common fractions they need to be reduced to a common denominator then to put numerators, having left a denominator without changes. The example of addition of fractions 1/2 and 1/3 is given in the drawing. The difference of fractions is the same way, after finding of a common denominator, numerators of fractions are subtracted, see an example in the drawing.
3. Multiplication and division of fractions. At multiplication of common fractions, numerators and denominators are multiplied among themselves. To divide two fractions, it is necessary to receive fraction the return the second fraction, i.e. to change its numerator and a denominator in places then to make multiplication of the received fractions.