Percent means per every hundred and denoted by the symbol %. A fraction with denominator 100 is called a Percent.

### 1. Profit and Loss

**Cost Price (CP):** Amount paid to buy an article.

**Selling Price (SP):** Amount at which an article is sold.

**Profit or Gain:** When SP > CP, the seller makes a profit or gain.

Gain = SP - CP

**Loss:** When CP > SP, the seller incurs a loss.

Loss = CP - SP

Gain and loss are always calculated on the CP.

**Gain %** = (Gain x 100)/CP

**Relation between SP and CP:** In case of Gain:

**Marked price or list price (MP):** Price at which a article is listed for sale.

**Discount:** Reduction in the marked price of an article.

**Net selling price (SP):** SP = MP - Discount

### 2. Interests

**Principal (P):** Money borrowed.

**Interest (I):** Extra or additional money paid by the borrower.

**Amount (A):** Total money paid by the borrower.

A = P + I or I = A – P

**Rate (R):** Interest on Rs. 100 for 1 year is known as the rate percent per annum.

**Simple Interest (SI):** Interest which is calculated uniformly on P throughout the loan period.

SI = (P x R x T)/100

**Compound Interest (CI):** Interest obtained during the first time period is added to the original P and amount becomes new P for the second time period and so on. The difference between the amount obtained at the last time period and original principal is called compound interest.