Percentage -1

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1. In a class, the number of girls are 40% more than number of boys.In an examination conducted in the class, 55 % of students failedin the exam. If 48% of boys failed in the exam, then what is the %of girls passed in the exam?

2. In a company, 60% of employees are women. If 40% of men and35% of women employees are untrained. Then what % ofemployees in the company are trained?

3. A man was recruited in the company with a salary of 12000/-.After 1st year, his salary was increased by 20%.After 2nd year, his salary was increased by 33 %.After 3rd year, his salary was decreased by 10%.After 4th year, his salary was increased by 25%.

What is the % change in his salary in 4 years ?COMSCIGUIDE

change = 100

error = 100• A = x % of B => if B = 100 then A = x• A = x % more than B => if B = 100 then A = 100 + x• A = x % less than B => if B = 100 then A = 100 – x• 100 % of any value is value itself.

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1. In a class, the number of girls are 40% more than number ofboys. In an examination conducted in the class, 55 % of studentsfailed in the exam. If 48% of boys failed in the exam, then what isthe % of girls passed in the exam?

Ans :Number of girls = 40 % more than boysBoys Girls Total100 140 240

55% of students are failed in the exam . So 45 % of students are passed.Therefore total number of students passed are 108.

100 % = 24045 % = 108100 % = 100 52% = 52

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Boys Girls Total100 140 240 -> strength52 56 108 -> passed

Similarly 52 % of the boys passed in the exam. Total no of boys passed are 52.Number of girls passed = number of students passed - number of boys passed

= 108 – 52= 56.

Number of girls passed = 56.% of girls passed in the exam is 40%

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% passed = 56ଵସ 100

In a company, 60% of employees are women. If 40% of men and35% of women employees are untrained. Then what % ofemployees in the company are trained?

2.

Women are 60%. Let the total number of employees are 100.=> Women are 60 and men 40

Men Women Total40 60 100 = Total24 39 63 = trained

Ans :

100 % = 6065 % = 39100 % = 40 60% = 24

Total number of employees trained are 63COMSCIGUIDE

A man was recruited in the company with a salary of 12000/-.After 1st year, his salary was increased by 20%.After 2nd year, his salary was increased by 33 %.After 3rd year, his salary was decreased by 10%.After 4th year, his salary was increased by 25%.

What is the % change in his salary in 4 years ?

3.

The general method that most of them use is calculating the total sum every year.But it takes a lot of time.

1st year = 144002nd year = 19200 % change =21600−12000

ଵଶ 1003rd year = 17280 = 80 %4th year = 21600

Ans :

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Doing the same question in 10 sec :Initially assume some money which is easy for doing calculations. It need not be the given amount for this method. I am assuming the amount as 100.

100 120 160 144 180

80% increase

Now consider the difference between the final and initial value

20 40 16 36

Percentage increase in his salary = 80 COMSCIGUIDE

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Continued…..

Problems for practice are given in the description of the video.

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10 % -> divide the value by 10100 % = 240 => 10 % = 24 => 5% = 1250 % = 12045 % = 108

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Practice problemson Percentage

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1. A train crosses a pole in 12 sec. It crosses a bridge of length 300m in 27sec. what is the time taken by the train to cross a bridge of length of 600m?

2. A train crosses a bridge of length 122m in 17 sec. it crossed another bridgeof length 210m in 25 sec. find the length of the train?

3. A train travelling at a speed of 54kmph crosses a platform in 36 sec and aman standing on the platform in 20 sec. find the length of the platform?

4. A train of length 240m travelling at a speed of 64kmph overtakes a manrunning at a speed of 10 kmph in __ sec ?

5. A train starts from a station X at 6am and reaches another station Y at 10am. Another train starts from station Y at 8am and reaches station ‘X’ at11:30am. At what time do the trains cross each other?

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1. In a class, the number of boys are 20% less than number of girls.In a test conducted in the class,70% of students failed in theexam. If 55% of boys failed in the exam, then what is the % ofgirls passed in the exam?

Ans :Number of boys = 20 % less than girlsBoys Girls Total80 100 180

55% of students are failed in the exam . So 45 % of students are passed.Therefore total number of students passed are 54.

100 % = 8045 % = 36100 % = 180 30% = 54

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Boys Girls Total80 100 180 -> strength36 18 54 -> passed

Similarly 52 % of the boys passed in the exam. Total no of boys passed are 52.Number of girls passed = number of students passed - number of boys passed

= 54 – 36= 18.

Number of girls passed = 18.

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