Question

Renu deposited a sum of 12500 in a bank for 3 years. If bank pays compound interest at
the rate of 6% per annum, what amount will she get at the end of 3 years ?
​

Answer 1

Answer:

Easy. Use the rule of 72, (it is a little off if you do the full math, but it’s “close enough for government work.”

72 divided by the interest rate equals the years to double.

72 /12.5=5.76 years to double, (so almost six years).

PS - unless you are in a time-machine and can go back to the 1970s, you will NOT find any bank paying 12.5%. And, if you have a stock that is paying that, be VERY careful, (unless it is a REIT or BDC

Answer 2

Step-by-step explanation:

Amount deposited every month, P= 500

Number of months, n=5×12=60 months

Rate of interest, r=721% =215%

Total deposit made =Pn=500×60

                               = 30,000

Period for recurring deposit, N=121[2n(n+1)] years

                                               =241×60×61=2305 years

Interest, I=100PNr

                 =500×2305×2×10015

                 = 5,718.75

Total amount due =Pn+100PNr

                            =30,000+5,718.75

                            = 35,718.75