CHAPTER 8 COMPARING QUANTITIES
To compare two quantities, their units must be the same.
If converting the ratios into fractions and then making them like fractions turns them into equal fractions, the ratios are equivalent ratios.
Percentage is how much the quantity is a part of a hundred.
CONVERTING FRACTIONS INTO PERCENTAGE
To convert fractions into percentage, multiply the fraction by 100.
CONVERTING DECIMALS INTO PERCENTAGE
Convert the decimal into fraction and then multiply it by 100.
CHANGE IN PERCENTAGE
To find out the change in any quantity in percentage,
% change = (Amount of change)/(Original amount) x 100
BUYING AND SELLING
The buying price of any item is called its cost price (CP). The price at which it is sold is called its selling price (SP).
Profit is when the SP is more than the CP.
Loss is when the CP is more than the SP.
If CP=SP, there is no profit, no loss.
% profit = Profit/CP x 100
% loss = Loss/( CP) x 100
The borrowed amount is called the principal.
The extra amount paid along with the principal is called the interest.
Simple Interest = (Principal x Rate x Time)/100