Question

the difference between the ci and si on certain sum of money at
10% for 3 years is rupees 93 find the sum

Answer 1

Let the sum be Ru 100.
here , R%= 10% p.a., n=3
C. I. = P[(1+R/100)^n-1]
= Ru 100[(1+10/100)^3-1]= Ru 100[(1+1/10)^3-1]
= Ru 100[(11/10)^3-1]= Ru 100 [1331/1000-1]
= Ru 100[1331-1000/1000]=Ru 100*331/1000
= Ru 33.10
Also, S.I.=P*R*n/100
= Run 100*10*3/100=Ru 30
therefore The difference between C.I. and S.I. is Ru 3.10,then the sum = Ru 100

If the difference between C.I. and S.I. is 1,then the sum = Ru 100/3.10

If the difference between the compound interest and the simple interest is Ru 93,then the sum = Run 100/3.10*93=Ru 3000

Hence the required sum is Ru 3,000