Question

Aslamchacha got Rs.100000 when he retired from his service. He deposited some of that
money in the bank and rest of his money in the post office and got 3400 in total per year
as interest. If the rates of simple interest per annum in the bank and in the post office are
3% and 6%, respectively, then let us write by calculating, the money he had deposited in
the bank and post office.
home time The​

Answer 1

Principal for Bank and PO is Rs.60000/- & Rs.40000/- respectively.

Step-by-step explanation:

Given, The total Principal deposited in Bank & Post office (P) = Rs. 100000 /-

Let the Principal deposited in Bank be Rs. x /- and that deposited in Post office becomes Rs. (100000 - x) /-

The Rate of interest for Bank and Post office are 5 % and 6% p.a. respectively.

The time for deposition is 1 year.

Using the Simple Interest formula -

Simple Interest (S.I.) = (Principal x rate x Time) / 100

So, In case of Bank, the S.I becomes {(x) x 5 x 1}/100 ''''''''''''''(1)

And that for Post office becomes, S.I. = {(100000 - x) x 6 x 1}/100 ''''''''''''''''''''(2)

We have been given the total interest as Rs. 5400 /-

Hence, addition of (1) and (2) yields the total interest obtained

which says, 5x/100 + (600000 - 6x)/100 = 5400

Taking LCM on the Left hand side of equation gives -

⇒ 5x - 6x + 600000 = 540000

⇒ - x = 540000 - 600000

⇒ - x = - 60000

So, x = 60000

Hence, the Principal deposited in Bank is Rs. 60000/- and

Post Office is (100000 - 60000) Rs. 40000/-