It would take 25 years for Birr 500 to quadruple if invested at a rate of 12% simple interest per annum.
Using the simple interest formula A = P(1 + rt) where
Since we require t, making t subject of the formula, we have
t = [(A/P) - 1]/r
Substituting the values of the variables into the equation, we have
t = [(A/P) - 1]/r
t = [(4P/P) - 1]/0.12
t = [4 - 1]/0.12
t = 3/0.12
t = 25 years
So, it would take 25 years for Birr 500 to quadruple if invested at a rate of 12% simple interest per annum.
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