Simple (Flat Rate) Interest Calculator: Calculate the Principal (Initial Starting Amount of Money) To Be Lent, Deposited or Borrowed With a Simple (Flat) Interest Rate in Order To Produce a Sum of Money of 210 Units (Dollar, Euro, Pound, etc.) for an Investment Duration Period of 202 Days (6 Months and 21 Days). Annual Simple (Flat) Interest Rate: 2%. Transaction Fee: 0.3%
Detailed calculations of the principal
Notations and variables used:
Principal (initial amount), P
Due interest, I = 210
Annual simple interest rate, R = 2%
From date: Sep 10, 2016
To date: Mar 31, 2017
Duration, T = 202 days (6 Months and 21 Days)
Transaction fee rate, F% = 0.3%
Transaction fee amount, F
Number of days in a year, N = 365
Calculate P, the principal (the initial amount of money to be lent, deposited or borrowed) to earn the simple (flat rate) interest
The simple (flat rate) interest calculation formula:
I = (P × R × T) ÷ N ⇒
P = (N × I) ÷ (R × T) =
(365 × 210) ÷ (2% × 202) =
(100 × 365 × 210) ÷ (2 × 202) =
7,665,000 ÷ 404 ≈
18,972.772277227723 ≈
18,972.77
Calculate E, the amount earned after adding the simple (flat rate) interest amount to the principal
E = P + I =
18,972.772277227723 + 210 =
19,182.772277227723 ≈
19,182.77
Calculate L, the amount left after deducting the transaction fee
F = F% × E ⇒
L = E - F =
E - F% × E =
(1 - F%) × E =
(1 - 0.3%) × 19,182.772277227723 =
99.7% × 19,182.772277227723 ≈
19,125.22396039604 ≈
19,125.22
Calculate Pr, the profit of the investment
Pr = L - P =
19,125.22396039604 - 18,972.772277227723 =
152.451683168317 ≈
152.45
Used symbols: % percent, ÷ divide, × multiply, = equal, ≈ approximately equal.
Writing numbers: comma ',' used as thousands separator, point '.' used as a decimal mark.
More operations with the simple (flat rate) interest, calculate the principal:
Calculate principal amount to invest to get a certain simple flat rate interest
Principal = (Number of days in a year × Simple flat rate interest) ÷ (Annual simple flat interest rate × Duration in days)