Quantitative Aptitude-Concepts and Theory updated on Dec 2021
The concept of percentage is required in many other quantitative aptitude topics Profit/Loss, Ratio/Proportion, Number theory and Data Interpretation also. Also, there is a separate section of percentages in the quantitative aptitude which holds good weightage and thus, percentage is considered as one of the most important topics. A percentage is a number or ratio expressed as a fraction of 100. So 20%, means 20/100. Percentage is one of the simplest tools for the comparison of data as it helps to compare between different fractions when the denominator or the total number is different in each case. Candidates should know the Best ways to work out percentages problems so that they can solve the problems quickly in the competitive exams.

Quantitative Aptitude

Percentages-Concepts and Theory

|   38550

Percentages  Aptitude basics, practice questions, answers and explanations 
Prepare for companies tests and interviews

 

Percentages
 

By a certain percent, we mean that many hundredths. Thus, x percent means x hundredths, written as x%.

To express x% as a fraction, we have x%=x/100.
Thus, 20%= 20/100= 1/5
To express a/b as a percent, we have, a/b= (a/b)*100%.
Thus, 1/4= (1/4)*100%= 25%.

1. If A is R% more than B, then B is less than A by R/ (100+R)*100
2. If A is R% less than B, then B is more than A by R/(100-R)*100
3. If the price of a commodity increases by R%, then reduction in consumption, not to increase the expenditure is: R/(100+R)*100
4. If the price of a commodity decreases by R%, then the increase in consumption, not to decrease the expenditure is: R/(100-R)*100

Results on population:

Let the population of a town be P now and suppose it increases at the rate of R% per annum, then;

1. Population after n years= p (1+(R/100))n
2. Population n years ago= P/(1+(R/100))n

3. If a number is increased by x% and thereafter reduced by x%, then the number will be reduced by x2/100 percent

4. If a number is reduced by x% and there after increased by x% then the number will be reduced by x2/100 percent

5. If in an examination, in which the minimum pass percentage is x%, a candidate secures y marks and falls by z marks, then the total number of marks in this examination will be 100*(y+z)/x

6. If in an examination x% and y% candidates respectively fail in two different subjects while z% candidates fail in both the subjects, then the percentage of candidates who pass in both the subjects will be [100-(x+y+z)]%

Tips:

1. If an object's price is increased or decreased by x% and the other factor is decreased by y% then the net effect is given by:
Net Effect= [x+y+xy/100]%

2. If the net effect is nil, ie, there is no loss or no gain, then the above formula becomes: y=100x/100+x

3. If the price of an article is successively increased by x%,y% and z% then single equivalent increase in the price will be [x+y+z+{xy+yz+zx}/(100)+xyz/1002]%

4. If after spending p1% first, then p2% from the remaining and so on, B is the balance amount, then the total (original) amount is given by:
Total amount= B*100*100...../ (100-p2).....

Population formula: 1)If the population increases by x% during the first year, by y% during the second year, by z% during the third year, the population after three years will be:
P(1+x/100)(1+y/100)(1+z/100)

The concept of percentage is required in many other quantitative aptitude topics Profit/Loss, Ratio/Proportion, Number theory and Data Interpretation also. Also, there is a separate section of percentages in the quantitative aptitude which holds good weightage and thus, percentage is considered as one of the most important topics. A percentage is a number or ratio expressed as a fraction of 100. So 20%, means 20/100. Percentage is one of the simplest tools for the comparison of data as it helps to compare between different fractions when the denominator or the total number is different in each case. Candidates should know the Best ways to work out percentages problems so that they can solve the problems quickly in the competitive exams. Freshersworld provides candidates with the questions and answers with explanations, aptitude test, Formulas, tips, tricks and shortcuts methods to solve the problems related to Percentages. How to Find Percentage of Marks Obtained? Divide the total scores with the marks obtained and then multiply the result with 100. What is 8 as percentage of 20? 40%
feedback