The income of a company increases by 20% per year, if income is Rs.28800 in year 2023, then its income in year 2021 was?

18000 21000 17000 20000

20000

A = P (1+\(\frac{R}{100}\) )T 28800 = P (1+ \(\frac{R}{100}\) )2 28800 = P ( 1 + \(\frac{20}{100}\)2 28800 = P ( \(\frac{6}{5}\)2 \(\frac{28800×5×5}{6×6}\) = P      P = 20000