When difference between compound

Rate = 4% , Time = 3 years
Difference between CI and SI for 3 years
CI - SI = $ P \left(\frac{r}{100}\right)^2 \left(3 + \frac{r}{100}\right) $
$ 228 = P \left(\frac{4}{100}\right)^2 \left(3 + \frac{4}{100}\right) $
$ 228 = P \times \frac{16}{10000} \times 3.04 $
$ 228 = P \times \frac{48.64}{10000} $
$ P = \frac{228 \times 10000}{48.64} $
P = 46875
Principal = ₹46875