Asked by lakshmi

a sum required to earn a monthly income of 1200 at 18% per annum then SI?
Answered by Ms. Sue
SI?

https://en.wikipedia.org/wiki/Si
Answered by MathMate
Since the period of time is not mentioned, it will be assumed that it is a perpetual annuity, with initial sum S generating interest of $1200 per month forever.
18% APR = 1.5% per month.
Therefore
S*0.015=1200, or
S=1200/0.015=80000