Quant Notes| Percentage
The term percent means "for every 100" It is derived from french word "cent" which is 100 for french.
In the context of business and economic performance, It is specifically, useful for comparing data such as profits, growth rates, magnitude and so on. Percentage and ratio are one of the most important topics that the topic of the base is clear as well as strong in that topic, then you cover most of the quant section. Most of them have changed their exam patterns and set a sectional timing of 20 minutes on each section. Quantitative aptitude is important for every exam because proper strategy and enough practice can help you score full marks in this section.
Notes-percentage represents the value obtained out of every 100, the calculation can be done in following - percentage=value obtained*100/total value
Eg. Let SBI clerk examination Rahul scored 135 marked out of 300 marks then marks obtained by Rahul in % term?
solution- 135*100/300=45%
In the context of business and economic performance, It is specifically, useful for comparing data such as profits, growth rates, magnitude and so on. Percentage and ratio are one of the most important topics that the topic of the base is clear as well as strong in that topic, then you cover most of the quant section. Most of them have changed their exam patterns and set a sectional timing of 20 minutes on each section. Quantitative aptitude is important for every exam because proper strategy and enough practice can help you score full marks in this section.
Notes-percentage represents the value obtained out of every 100, the calculation can be done in following - percentage=value obtained*100/total value
Eg. Let SBI clerk examination Rahul scored 135 marked out of 300 marks then marks obtained by Rahul in % term?
solution- 135*100/300=45%
Percentage to fraction-
Eg. 1. 35%=7/20
2. 32%=8/25
3. 84%=21/25
Some important faction to percentage value-
| Fraction | Percentage |
|---|---|
| 1/100 | 1% |
| 1/2 | 50% |
| 1/3 | 33.33% |
| 1/4 | 25% |
| 1/5 | 20% |
| 1/6 | 16.66% |
| 1/7 | 14 2⁄7 =14.28% |
| 1/8 | 121⁄2 =12.5% |
| 1/10 | 10% |
| 1/12 | 81⁄3 =8.33% |
| 1/16 | 61⁄4=6.25% |
| 3/4 | 75% |
| 4/5 | 80% |
Type1-
If x% of A is equal to y% of B then z% of A= (xy/z)
Solution-
Here x=10 , y=12 and z=15,
15% of A ( 12*15/10 )% of BType2-
When a number x is increased or decreased by y% then the new number will be- ( 100±y/100 )*x
Notes- (+) sign used in case of increase
(-) sign used in case of an increase
Eg. The monthly income of Ram is ₹ 12000. If his income is increased by 20%, then what will be his new monthly income?
Solution-
Increament in income=12000*20/100= ₹ 2400 .
new income= 12000+2400= ₹ 14400.
Type3-
If x is a% more than y then y is ( a / 100+a )x100% less than x .
If x is a% more than y then y is ( a / 100-a )x100% more than x.
Eg. 1. If the Income of Rehaan is 40% than that of Ram, the income of Ram is how much percent less that of Rehaan?
Solution-
Let the Ram income be 100
Then, Rehaan income=140
required percentage = 40/140 % =2/7 %
Eg.2. If the price of sugar increased by 25% find how much percent its consumption be reduced so as not increase the expenditure?
Solution-
Required consumption = 25/125%=20%
Type4-
If the present population of time (or value of an item) be the 'T' and the population(or value of the item) in R% per annum, then
Eg. The population of a town increases by 10% annually. If its present population is 120000, what will it be in 2 years time?
Solution-
=12000 x 110 x 110
100 100
=145200
Type5-
1. The passing marks in an examination are x% if a candidate who scores y marks fail by z marks, then the maximum marks,
2. A candidate scores x% in an examination and fails by ‘a’ marks, while another candidate scores y% marks and he gets ‘b’ marks more than the minimum passing marks. Then, the maximum marks of the examination
.Eg. A candidates score 25% marks and fail by 30 marks, while other candidates who score 50% marks, get 20 marks more than the minimum required marks to pass the examination. What are the maximum marks in the examination?
Solution-
Maximum marks=
=>Basic Practice Question:-
1. A student has to score 30% marks to get through. If he gets 30 marks and fails by 30 marks, then find the maximum marks set for the examination.Solution-
Let the maximum marks be X
According to the question,
30X/100 = (30+30) → 30X/100 = 60 → X = 200
2. In an examination, 20% of the total number of students failed in History, 15% of the total number of students failed in Hindi and 5% of the total number of students failed in both. Find the percentage of students, who passed in both the subjects.
Solution-
Let total number of students be 100
Then, students failed in History only = 20 – 5 = 15
And Students failed in Hindi only = 15 – 5 = 10
⸫ Total number of failed students = 15+10+5=30
⸫ Number of passed students in both the subject = 100-30= 70
⸫ Required percentage = 70%
3. A man had Rs 24000 in his bank account 2 years ago. In the first year, he deposited 20% of the amount in his bank account balance. In the second year, he deposited 25% of the increased amount in his account. What is the deposit amount of present in his bank account?
Solution-
Presently, the deposit amount in his bank account.
4. The population of a town is decreased by 20% and 30% in two successive years. What percent of the population decreases after two years?
Solution-
Here x=-20 y=-30
Net change=
Population decrease by 44%
4. In expressing a length 81.472 km as nearly as possible with three significant digits, find the percentage error.
Solution-
5. Sixty-five percent of a number is 21 less than four-fifth of that number. What is the number?
