Simple Interest Formula

Interest is computed once, on the original principal, then accrues at the same flat amount each period.

The formula

Bₙ = B₀ + n · R · B₀

Interest calculated linearly on the original principal — no compounding.

What goes into it

Initial borrowed capital (B₀)
Number of periods (n)
Interest rate per period (R, %)

Worked example

Principal (B₀)	$100
Rate / period (R)	7%
Periods (n)	5
Balance B₅	$135

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