Percentage (प्रतिशत) – Basics & Definition (SSC CGL Maths)

Basics First Hinglish Notes SSC Ready

Ye page sirf Basics/Definition ke liye hai: % kya hota hai, kab use hota hai, aur percentage chapter me kaun-kaun se topics aate hain.

Quick TOC

Percentage kya hai?
Kab aur kahan use hota hai?
Percentage chapter me topics
Conversions (Fraction/Decimal/Ratio ⇄ %)
Base concept: p% of N
SSC ke common patterns
Solved examples
Practice + answers

1) Percentage kya hai?

Percent ka matlab hota hai “per 100” यानी 100 me se.

x% = x/100

1% = 100 me se 1 part
50% = aadha (1/2)
100% = poora (1)

Core line: “% ko fraction/decimal me le jao aur calculation easy ho jaati hai.”

2) Kab aur kahan use hota hai?

Percentage ka use tab hota hai jab hum comparison karna chahte hain (part vs whole) ya change measure karna ho (increase/decrease).

Area	Use case
Profit–Loss / Discount	Profit %, Loss %, Discount %
SI–CI	Rate %, growth factor
DI / Data	Share %, growth %, comparison
Population / Depreciation	Yearly increase/decrease
Expenditure	Price×Quantity me net % change

3) Percentage chapter me kaun se topics aate hain?

Definition + basic conversions (fraction/decimal/ratio ⇄ %)
p% of a number aur “given % value se original nikaalna”
Comparison: A is x% of B, x% more/less than
Percentage change: increase/decrease ka intro (base = old)
Successive change (multiple % changes)
Reverse percentage (final diya ho to original)
Applications: profit-loss, discount, SI/CI, population, DI, expenditure

Next pages typically: Increase–Decrease, Successive %, Reverse % etc. (Aap chahe to main internal links bhi add kar dunga.)

4) Conversions (Fraction/Decimal/Ratio ⇄ %)

% = Decimal × 100

Decimal = % ÷ 100

Fraction a/b ⇒ % = (a/b)×100

Fraction/Decimal	Percentage	Fast memory
1/2	50%	Half
1/4	25%	Quarter
3/4	75%	25% less than 100
1/5	20%	Divide by 5
1/8	12.5%	Very common
0.3	30%	×100
0.075	7.5%	Shift 2 places

SSC tip: 12.5% = 1/8, 16.66% ≈ 1/6, 33.33% = 1/3, 66.66% = 2/3 (DI me kaafi help).

5) Base concept: p% of N

Kisi number N ka p%:

p% of N = (p/100) × N

Agar diya ho “p% of N = V”, aur N nikaalna ho:

N = (V × 100) / p

Shortcut	Meaning
10%	N/10
5%	10% ka half = N/20
1%	N/100
12.5%	N/8
25%	N/4

Golden rule: “% nikalna hai to number ko fraction bana do.”

6) SSC ke common patterns (Basics level)

Type	Template	Fast line
A is x% of B	A = (x/100)×B	B = (A×100)/x
A is x% more than B	A = B×(100+x)/100	Factor method
A is x% less than B	A = B×(100−x)/100	Factor method
B is what % less than A?	(A−B)/A×100	Base = “jisse compare”

Base warning (SSC trap): “less than A” me divide A se hota hai, “less than B” me divide B se.

7) Solved Examples (Basics)

Example 1: 15% of 360

10% = 36, 5% = 18 ⇒ 15% = 54

Example 2: 12% of N = 96, N?

N = (96×100)/12 = 800

Example 3: A is 25% more than B

Assume B = 100 ⇒ A = 125

Is type me units method sabse fast.

Example 4: 80 is what % of 200?

(80/200)×100 = 40%

8) Practice (Basics) + Answers

640 ka 12.5% nikaalo.
18% of N = 270, N nikaalo.
45 is what % of 360?
A is 20% more than B. If B = 250, A?
A is 30% less than B. If B = 500, A?
300 ka 7% nikaalo (fast).
120 is what % of 96?
1% of a number is 9. Number?

Show Answers

12.5% = 1/8 ⇒ 640/8 = 80
N = 270×100/18 = 1500
45/360×100 = 12.5%
A = 250×1.2 = 300
A = 500×0.7 = 350
7% = 5%+2% ⇒ 15 + 6 = 21
120/96×100 = 125%
Number = 9×100 = 900

Next step: Percentage Change (Increase–Decrease) wala page—wahi se SSC ke heavy questions start hote hain.