Interest on money

Introduction to Simple Interest

• Definition of Simple Interest: Simple interest is the amount charged or earned on a principal sum of money over a certain period at a specific interest rate.

Key Components for Calculating Simple Interest

• To calculate simple interest, three variables are essential:

  • Principal (P): The original sum of money borrowed or invested.

  • Rate (R): The interest rate charged or earned, expressed as a decimal.

  • Time (T): The duration for which the money is borrowed or invested, typically measured in years.

Simple Interest Formula

• The formula for calculating simple interest (I) is given by:

  • I = P \times R \times T

  • Where:

  • I = Interest

  • P = Principal amount

  • R = Rate of interest (as a decimal)

  • T = Time (in years)

Example Calculation of Simple Interest

• Given values for the example:

  • Principal (P) = $200

  • Rate (R) = 10% = \frac{10}{100} = \frac{1}{10}

  • Time (T) = 2 years

• Step-by-step calculation:

  1. Substitute the known values into the formula:

  • I = P \times R \times T

  • I = 200 \times \frac{1}{10} \times 2

  1. Calculate the interest:

  • I = 200 \times 0.1 \times 2

  • I = 200 \times 0.2

  • I = 40

• Result:

  • The calculated simple interest for borrowing $200 for two years at a rate of 10% is $40.

Implications of Simple Interest Calculation

• Loan Repayment: This means that if you borrow $200 from the bank at a 10% annual interest rate for two years, by the end of the loan term, you will owe the bank an additional amount of $40 in interest.

  • Total amount to repay:

  • Total repayment = Principal + Interest

  • Total repayment = $200 + $40 = $240

  • Thus, the total amount owed at the end of two years will be $240.