Concept of Percentage
By certain percent , we mean that many hundredths. For example by x percent we mean x hundredth and denote it as x%.
In Fraction x% is expressed as x% = x/100.
A fraction (a/b) can be converted into fraction as : - (a/b) x 100 %
Balancing expenditure :
We can balance our expenditure by reduction or increase in certain percentage of consumption of commodity when ever their is certain percentage of increase or decrease in commodity price respectively.
Formulae Used
If the price of a commodity increases by R%, then to keep our expenditure constant we should reduce its consumption by
[ {R / ( 100 + R)} x 100] %
If the price of a commodity decreases by R%, then to keep our expenditure constant we can increase its consumption by
[ {R / ( 100 - R)} x 100] %
Where R is the increase/decrease percentage of price of commodity
