The whole positive numbers, since unit are called natural. The fraction is number too, but it expresses not quantity of the whole objects, but quantity of shares of unit. Such numbers by certain rules are multiplied.
Instruction
1. In mathematics actions with fractionsof simple and decimal are taken. The decimal fraction shows the number of the tenth (the 100-th, thousand) add whole. I.e. at operations with decimal fractions the division whole on quantity of shares, multiple to ten is supposed. The decimal fraction registers in format 0, hkhkh.
2. The simple fraction allows to express any part of number and registers in the form of two-storeyed number. The top part of fractional number is called numerator, lower — a fraction denominator. The denominator shows into how many parts the whole unit is divided. The numerator is equal to quantity of such shares in fractional number.
3. The result of multiplication of fraction by natural number can be less whole, it is more whole or is equal to whole. For example, the tenth part of whole can be written down in the form of decimal fraction 0.1 or simple fraction 1/10. Five times on 1/10 are less than a single whole. Ten times on 1/10 - correspond to one unit and if to take 12 times on 1/10, more single whole will turn out.
4. To increase simple fraction by natural number, it is necessary to increase by this number only fraction numerator, and to leave a denominator without changes. If the result of multiplication is less than unit, the numerator of simple fraction is less than denominator. Such fraction is called proper. At multiplication of simple fraction by natural number, bigger a denominator, the number more than unit turns out. Such number in fractional record represents an improper fraction in which the numerator is more than a denominator. The improper fraction can be changed in mixed, consisting of the whole and fractional parts. For example, at multiplication it turns out 3/4 on 5 15/4 or 3 ¾.
5. At multiplication of decimal fraction by natural number find the work of this natural number and significant figures of decimal fraction. In the received number separate on the right as much signs how many was in the multiplied decimal fraction after a comma. For example: 0.17*24. 17*24=408. In fraction 0.17 two figures after a comma, mean in number 408 a digit comma put after two figures on the right: 4.08 Result of multiplication 0.17*24=4.08.