’p’ is considered the principal AMOUNT

’r’ is considered the rate of interest

’t’ is considered the number of years

C.I is the compound interest

‘n’ is the number of TIMES compound interest is calculated in a year

‘A’ is the final amount after the compound interest

For the first year:

We know that

$({\rm{A\;}} = {\rm{\;p\;}} \times {\rm{\;}}(1{\rm{\;}} + \frac{r}{{100\; \times \;n}})$)^{(n × t)}

 $(\therefore {\rm{\;A\;}} = {\rm{\;}}21,000{\rm{\;}} \times {\rm{\;}}\left( {1{\rm{\;}} + {\rm{\;}}\frac{{25}}{{100\; \times \;2}}} \right))$^{(1 × 2)}

∴ A = 26578.125

Thus the MONEY Mr.Chopra got after year 1 is RS 26578.125

This will be the principal amount for the 2^nd year

For the second year:

$({\rm{A\;}} = {\rm{\;p\;}} \times {\rm{\;}}(1{\rm{\;}} + {\rm{\;}}\frac{r}{{100\; \times \;n}})$)^{(n × t)}

∴ A = 26578.125 × (1 + 25/100)

∴ A = 33222.65