If compound interest for 4th year is Rs.3000 @ 10% p.a. then find the compound interest for 8th year.

Rs. 4392.3

10% = \(\frac{1}{10}\)

Ratio of Principal to Amount = 10 : 11

         4th Year   :     8th Year

             10⁴      :       11⁴

⇒        10000    :     14641

⇒ 10000R = 3000 (given)

⇒ 1R = \(\frac{3}{10}\)

⇒ 14641R = 14641 × \(\frac{3}{10}\) = 4392.3/-