Question

a man deposited Rs 8000 in bank on 28th march, 2001 and closes his account on 21st august, 2001, if the bank allows an interest of 8% per annum, what amount does he get?​

Answer 1

It is given that the man deposited Rs 10000 in a bank at the rate of 5% simple interest annually. Since, the simple interest is added every year, the amount in every year is a term in arithmetic progression.

Formula for Simple Interest I =

$\frac{p \times r \times t}{100}$

Interest for each year =

$\frac{5}{100} \times rs10000 \\ = rs500$

Interest for each year is the common difference.

Formula for n

th

term in an AP t

n

=a+(n−1)d

Amount in 15th year =10000+14(500)

=17000

Amount after 20 years, which is amount in 21st year=10000+20(500)

=20000