Percentage-% Change YouTube Lecture Handouts for NET, IAS, State-SET (KSET, WBSET, MPSET, etc.), GATE, CUET, Olympiads etc.
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Percent Change Problems (Aptitude) : 15 Sec Shortcut Tricks (Marks, Population, Area)
Percentage-% Change
If the Sides of Cube is Increased by 100% . Find the % Change in Its Area. What About Volume?
There are 3 cubes whose size increased by 200% 1st cube to 2nd cube and increased by 300% 1st cube to 3rd cube that is change in the side of the cube and substitute problem would ask me what would be corresponding percent change in the area, surface area of the cube and volume of the cube.
Change
Side of the cube increased by 100%
Surface area of cube
If the Base Radius of a Right Circular Cylinder is Increased by 15% , and Its Height is Reduced by 20% , Find the Percentage Change in Its Volume
Formula of a right circular cylinder
Radius because increased by 15%
Its height is reduced by 20%
You can and would be canceling out.
Remember that % change is always with respect to the original quantity if nothing else is specified the problem.
Krishna՚s Salary is 20% Less Than Radha. By What % is Radha՚s Salary More Than Krishana?
There are two person Krishna and Radha.
Radha salary
Krishna՚s salary is 20% less than Radha so, Krishna salary
Which Would Produce Greater Net Income on Gross of 2000? 10% Tax over 200 ₹ 12% Tax over 400 ₹
10% tax over 200
12% tax over 400
Extra
A Labour Works 60 Hr. Per Week and He Earns ₹ 2400. If His Per Hour Salary is Increased by 16% and Hours Reduced by 20% . Find the % Change in His Income
Let assume is salary (increased 16%)
(Reduce 20%)
So,
% Change
Original value
If the Numerator of a Fraction is Increased by 200% and the Denominator is Increased by 360% , the Resultant Fraction is 5⟋12. What Was the Original Fraction?
Let՚s assume the fraction would be
If the Income Tax Were to be Increased by 19% then Net Income is Reduced by 1% . Find the Current Rate of Income Tax
100% increase in tax reduction income
19% increase in tax 1% income
Tax and Income
Gross income
Calculate the tax: gross income is made up of I and 19T
The Population of a Village is 9600. If the Males and Females Are Increased by 8% and 5% , then Population Will Become 10,272 After 1 Year. Find the Number of Males at Present
Total population of a village
We assume 100m (Male) and 100f (Female)
Increased by 5%
Difference
Difference of male:
In a Town, the Population Was 8000. In One Year, Male Population Increased by 10% and Female Population Increased by 8% but the Total Population Increased by 9% . The Number of Males in the Town Was?
Population
Assume that 100m and 100f
Increase everything by
Male and female
The total population increased by 9%:
Difference:
Therefore, the number of 40 males in the town.
When a Student Scores 30% Marks then He Fails by 5 Marks. However, when He Score 40% Marks then He Gets 10 More Than Passing Marks. Find Maximum Marks. What About Passing % ?
Here, there are two scale: relative scale and absolute mark
Difference
Mark
Total mark
Passing mark
Passing
Next Class-% Expenditure, Commission, Salary, & Bonus
✍ Mayank