Quantities can be compared in terms of more, less or equal or by assigning a numerical value in terms of a unit of measurement. For example: weight, distance, height, etc. can be compared.
Ratio is the comparison of two or more quantities of same kind by division. To find the ratio of the two quantities, both the quantities must be of the same kind and the same unit. While comparing ratios if the like fractions of given two ratios are equal, then the ratios are equivalent.
If two ratios are equal, then they are in proportion and the symbol for proportionality is ‘::’ or ‘=’.
Four numbers a, b, c and d are said to be in proportion, if the ratio of the first two is equal to the ratio of the last two, i.e., a : b :: c : d.
The method in which the value of a unit quantity is first obtained to find the value of required quantity is called the unitary method.
Another way of comparing quantities is percentage. Percentage is the numerator of a fraction with denominator 100.
Fractions and decimals can be converted into percentage and vice-versa. A fraction can be converted to percentage by multiplying with 100. A decimal can be converted to percentage by multiplying with 100. The percentage can be converted to fractions as well as in decimal number by dividing with 100.
One quantity can be expressed as the percentage of another. In order to find the percentage of a given quantity, the percentage will be first converted into fraction and then, it will be multiplied by the given quantity.
Profit or loss occurs while selling or buying an item. Profit and loss can be expressed as profit percentage and loss percentage which are calculated on cost price.
On depositing money in the bank, it gives an interest in the form of some extra money. That money is called interest. Interest earned depends on three factors namely, principal, the rate of interest and the time period.
Amount = Principal + Simple Interest
Keywords: Selling price