Question

Find the principal that will yield an interest of Rs.680 in 4 yr at 8% per annum.

Answer 1

let the principal be p
we know that p+simple interest=amount
p +s.i=680
p+[p*r*t/100]=680
p+[p*8*4/100]=680
p+32p/100=680
p+(8p/25)=680
(33p/25)=680
p=(680×25)/33
=17000/33
 =515.15 ruppes
principal is 515.15 ruppes