Question

What is the ROI in economic consideration of corrosion?

(a) Refund on investment

(b) Return on investment

(c) Refund on income

(d) Return on income

This question was addressed to me in an interview.

The doubt is from Principles in section Corrosion Principles of Corrosion Engineering

Answer 1

The correct option is (b) Return on investment

For explanation I would say: ROI means Return on investment.

 ROI=[(Oa+Ia/na)–(Ob+Ib/nb)/Ib–Ia]*100 where O = annual costs including maintenance cost, I=Investment, n=anticipated life in years, and subscripts a and b refer to the present and proposed installations, respectively.