Percentage (Aptitude) YouTube Lecture Handouts for NET, IAS, State-SET (KSET, WBSET, MPSET, etc.), GATE, CUET, Olympiads etc. (Precents Basis)
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Percentage Basics - 1 Key Trick (for Aptitude) : Working and Thinking in Relative Quantities
Key Ideas
- Fractions, Rations and percent- relative quantities
- Relative quantities and absolute quantities are not to be mixed.
- Relative quantities can be added or subtracted.
- x represents the unknown in the relative quantity.
If a = X % of Y and B = Y % of X, Then
- X > Y
- A > B
- Y < X
- A = B
Percentage
There are verities of problems based on percentage. We would be covering basic concepts of today which is Basic Formula and Basic Concepts
Let us very briefly cover what percentage actually means.
This diagram clearly summarized the concept. Here there are total of 100 squares out of each 3 are sky. This fact is represents in several ways:
- Fraction
- Decimal
- Percentage
In general
Relative Quantities- Fractions, Rations & Percent
Similarly, this pizza that the slice represent no matter what the size of pizza.
Here, he had two blocks, in these particular bar I have total of 4 yellow, 2 brown and 2 red blocks.
Here each of red and brown and 2 of yellow.
Relative quantities of yellow, red and brown block in each of these two bars is same.
In smaller bars, quantities of red block and yellow block it represented as fraction
Ratio of the small bar in terms of red block
In same fact can be representing as percentage so, we want to convert of red blocks.
Key Ideas
1. Fractions, ratios, and percent- relative quantities
2. Relative quantities and absolute quantities are not to be mixed.
3. Relative quantities can be added or subtracted
4. x represents the unknown in the relative quantity.
The
What Percent is 60 of 240?
Total of 240 reduce 100.
Percent
Find Sales Tax@20% from a Gross Figure of ₹ 1600?
If 50% of of , then What Percent of is
Trick about this question is what percent of x is y:
If 10% of a Number is Added with Itself then Result Becomes 1331. Find the Original Number
Here, we assume the relative number is it becomes
The original number is 1210.
60% of a Number is 360. What is 99% of the Same Number?
If 15% of a Number is Subtracted from Itself then Result Becomes 2550. Find the Original Number
Here, 15 is subtracted is 85
If 39 is Added in a Number, It Becomes 113% of Itself. Find the Number
We assume that
Number added
A House Sold for 357000 Dollars, Produces a Profit of 19% , Find the Profit?
Assume that the house
40% of 70 is What % More Than 30% of 80?
40% of 70
30% of 80
A Fruit Seller Had Some Apples. He Sells 40% Apples and Still Has 420 Apples. Originally, He Had?
come out to be
So,
If of Y and of X, Then
a.
b.
c.
d.
of Y
of X
So,
Hence,
A Number Exceeds 20% of Itself by 40. Find the Number?
Assume the number and it self
A Man Multiplied a Number by Instead of . What is % Error?
We assume that
We can assume ,
Number by
The Total Salary of a and B is ₹ 1500. A Spent 90% of His Income and B Spent 80% of His Income. The Ratio of Saving is 3: 4. Find the Ratio of Their Salary. What is Their Absolute Salary?
We assume that A salary
B salary
A spent 90% so, A spent
B spent 80% so, B spent
If I have a ₹ 5,3 would go to x and 2 would go to y.
We can multiply by 300 so,
and
Their absolute salary was .
If a Exceeds B by , B is Less Than C by , then Is
Here,
Next Class:% Change, Income & Consumption
The price of sugar decreases by 30% . By what % the consumption should increase so that expenditure decreases only by 10% ?
A man spends ₹ 5700 from his income of ₹ 8550. If his income and expenditure are increased by 19% and 13% . Find the % change in saving?
✍ Mayank