Hi Jin
To calculate ROI, you must calculate the net present value (NPV) applied the formula NPV = Sum (Fi (1 + i) ^-j), using a i (discount rate) you get a positive NPV and another the NPV is negative, then apply the formula
TIR = (ip + (VPN (IP) / (VPN (IP) VPN + absolute value (iq)) (iq-ip) * 100
ip <iq
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Edmundo Pimentel
Teacher
Calle Los Laboratorios
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