The difference between interest on 9th year and 8th year is the interest on interest for the 8th year please explain this statement with an example taking 100x

Hi
I will explain you for lesser values i.e when time is less and you can apply it similarly for all values
Let principal be 100x and R be 10 %
Now the interest for the first year is 10x(PR/100)
Now for the second year we again get this 10x and we have to add interest on interest accumulated
i.e interest for 2nd year will be 10x + 10/100 *10x = 10x+x=11x
Now for the third year we will get
10x + ( Total interest till 3rd year ) on interest
i.e we get 10x+(10x+10x+x)*10/100 = 10x+2.1x =12.1x
so interest for 3rd year is 12.1 x .
You can similarly solve for all the values proceeding in the similar manner.