Basics of Mathematics

                               Proportion is the Relationship b/w two Ratios.

   There are two main types of proportion/variation.  

1) Direct proportion/ variation

2)Inverse proportion/variation 

 A proportion in which one quantity is  increase/decrease and another quantity  are also  increase/decrease  then this type of proportion is know as direct proportion .

for example:

prize of 5 pens are RS 50 ,if you  have 100 rupees ,how many pens you purchase?

answer : we purchase 10 pens . 

In this question quantity of pens are increase because the rupees are also increase . 

A variation in which one quantity is increase but another is decrease them this type of variation is know as Inverse variation. 

for example:  5 masons can complete a building in 10 months ,10 masons can complete the same work in how many months?

answer:  5 months 

in this question the quantity of masons are increase but the months are decrease it is known as Inverse variation.