PPT - Proportions, "Ratio, Proportions, indices and logarithms" CA Foundation Notes | EduRev

 Page 1


Ratio and Proportion,  
Indices and Logarithm 
Paper 4: Quantitative Aptitude- Mathematics Chapter 1 
Part II: Proportion 
 
Ms. Ritu Gupta, MA (Maths.) 
Page 2


Ratio and Proportion,  
Indices and Logarithm 
Paper 4: Quantitative Aptitude- Mathematics Chapter 1 
Part II: Proportion 
 
Ms. Ritu Gupta, MA (Maths.) 
Learning Objectives 
What is 
proportion  
Properties of 
Proportion 
and its 
application 
2 
Page 3


Ratio and Proportion,  
Indices and Logarithm 
Paper 4: Quantitative Aptitude- Mathematics Chapter 1 
Part II: Proportion 
 
Ms. Ritu Gupta, MA (Maths.) 
Learning Objectives 
What is 
proportion  
Properties of 
Proportion 
and its 
application 
2 
Proportion  
• An equality of two ratio is called a proportion / Four 
quantities a, b, c, d are said to in the proportion if a : b = c : d 
(also written as a : b :: c : d) i.e. a/b = c/d i.e. if ad = bc. 
• The term a and d are called extremes, the term b and c are 
called the means. The fourth term d is called the fourth 
proportional of a, b and c taken in order. 
• If a:b :: b:c, then a, b, c are called in continued proportion, b 
is called the mean proportional between a and c and c is 
called the third proportional of a and b.  
3 
Page 4


Ratio and Proportion,  
Indices and Logarithm 
Paper 4: Quantitative Aptitude- Mathematics Chapter 1 
Part II: Proportion 
 
Ms. Ritu Gupta, MA (Maths.) 
Learning Objectives 
What is 
proportion  
Properties of 
Proportion 
and its 
application 
2 
Proportion  
• An equality of two ratio is called a proportion / Four 
quantities a, b, c, d are said to in the proportion if a : b = c : d 
(also written as a : b :: c : d) i.e. a/b = c/d i.e. if ad = bc. 
• The term a and d are called extremes, the term b and c are 
called the means. The fourth term d is called the fourth 
proportional of a, b and c taken in order. 
• If a:b :: b:c, then a, b, c are called in continued proportion, b 
is called the mean proportional between a and c and c is 
called the third proportional of a and b.  
3 
Properties  - Cross-multiplication 
4 
Page 5


Ratio and Proportion,  
Indices and Logarithm 
Paper 4: Quantitative Aptitude- Mathematics Chapter 1 
Part II: Proportion 
 
Ms. Ritu Gupta, MA (Maths.) 
Learning Objectives 
What is 
proportion  
Properties of 
Proportion 
and its 
application 
2 
Proportion  
• An equality of two ratio is called a proportion / Four 
quantities a, b, c, d are said to in the proportion if a : b = c : d 
(also written as a : b :: c : d) i.e. a/b = c/d i.e. if ad = bc. 
• The term a and d are called extremes, the term b and c are 
called the means. The fourth term d is called the fourth 
proportional of a, b and c taken in order. 
• If a:b :: b:c, then a, b, c are called in continued proportion, b 
is called the mean proportional between a and c and c is 
called the third proportional of a and b.  
3 
Properties  - Cross-multiplication 
4 
Properties - Invertendo 
5