In this article, we provide you a short and effective summary for Percentages. We cover a list of 15 formulas and short-cuts that you can use for Percentage questions. The following is a list of important formulas for Percentage:

**1.** Percent implies “for every hundred”.

% is read as percentage and x % is read as x per cent.

**2.** To calculate p % of y

(p/100) x y = (p x y)/100

p % of y = y % of p

**3.** To find what percentage of x is y: y/x × 100

**4.** To calculate percentage change in value

Percentage change = {change/(initial value)} x 100

**5.** Percentage point change = Difference of two percentage figures

**6.** Increase N by S % = N( 1+ S/100 )

**7.** Decrease N by S % = N (1 – S/100)

**8.** If the value of an item goes up/down by x%, the percentage reduction/increment to be now made to bring it back to the original point is 100x/ (100 + x) %.

**9.** If A is x% more /less than B, then B is 100x/(100 + x) % less/more than A.

**10.** If the price of an item goes up/down by x %, then the quantity consumed should be reduced by 100x/ (100 + x)% so that the total expenditure remains the same.

**11.** Successive Percentage Change

If there are successive percentage increases of a % and b%, the effective percentage increase is:

{(a + b + (ab/100)}%

**12. Percentage – Ratio Equivalence:**

*N is Numerator*

* D is the Denominator*

**13.** Product Stability Ratio:

A × B = P

If A is increased by a certain percentage, then B is required to be decreased by a certain percentage to keep the product P stable.

Expressing the percentage figures in ratios:

### Percentages: The Complete Lesson

#### Table of Contents

**Concept Articles**

**Exercises**

**Tests**