Ratio and proportion. Proportionality Ratio. Proportion ( border and middle terms ).The main property of a proportion. Proportional values. Factor of a proportionality. Ratio is a quotient of dividing one number by another. Proportion – an equality of two ratios. For instance: 12 : 20 = 3 : 5; a : b = c : d . Border terms of … [Read more...]

## Percents

Percents Percent. Three main problems by percents. Percent is a hundredth part of unit. A record 1% means 0.01. There are three main problems by percents: Problem 1. Find an indicated percent of a given number. The given number is multiplied by the indicated number of percents; then a product is divided by 100. E x a m p l e . A … [Read more...]

## Converting a decimal to a vulgar fraction and back

Converting a decimal to a vulgar fraction and back To convert a decimal to a vulgar fraction it is necessary: a number after a decimal point to make as the numerator, and the n-th power of 10 ( here n – a quantity of decimal places ) - as the denominator. A non-zero integer part of a decimal is saved the same in a vulgar fraction; a zero integer part is omitted. For … [Read more...]

## Operations with decimal fractions

Operations with decimal fractions Addition and subtraction of decimals. Multiplication of decimals.Division of decimals. Division of decimal fraction by integer. Division of decimal fraction by another one. Addition and subtraction of decimals. These operations are executed as well as an addition and a subtraction of whole numbers. It is only necessary to write the … [Read more...]

## Decimal fractions (decimals)

Decimal fractions (decimals) Decimal fractions (decimal point, decimal places). Properties of decimals. Repeating decimals. Decimal fraction is a result of dividing of unit by ten, hundred, thousand parts etc. These fractions are very comfortable in calculations, because they are based on the same system, that calculus and record of integers are built. Due to this … [Read more...]