Different techniques for solving Interest Related Math

Various (short) rules of solving mathematical problems:

Basically, all problems can be solved by only two sources of interest.

(a) i= 100.

(b) P= C (1+rt/100)

Here, I= Interest, C= Capital, r= rate of interest, t= time (in year) &

P= Capital+Interest 

Details Formulas:

Source: 1

When the value of money or real, time and interest rate is given:

Interest or profit = (money x time x interest rate) / 100

অর্থাৎ, I=Crt/100, here, I= Interest, C= Capital, r= rate of interest, t= time (in year)

Question: what is the interest of 500 % of 3 years in simple interest?

Solution:

100 = 100, interest / profit = (500 x 3 x 10) / 100 = 150 = 150 tk

Question: what will be the rate of 5 years per cent per year?

Solution:

In the same way, i=crt / 100

Or, R= (I x 100)/ (c x to)

Interest Rate = (140 x 100) / (400 x 5) = 7 TAKA

Question: how much money will be rs. 4 per cent per cent per cent per cent?

Solution:

In the same way, i=crt / 100, or, = (100 x) / (100 x) / (100 x)

Good, capital = (84 x 100); (6 X 4) = 350 taka

Source: 2

When interest, money and interest rates are given -

Time = (interest x 100) / (Capital x interest rate)

That means, it is easy to solve all questions if one mind is in a mind.

I=Crt/100, here, I= Interest, C= Capital, r= rate of interest, t= time (in year)

Or, t = (100 x I) / (c x r)

Question: how much will be the profit of 600 rupees at 4 % rate?

Solution:

To = (100 x I) / (c x r)

IE, time = (120 x 100) / (600 x 4) / (600 x 4 = 5 years)

Source: 3

When the price is quality and the rate of interest is mentioned then -

Time = (number of times-1) / interest rate x 100

We know the main source of interest (in the year 100)

New one term original-interest or slave or suda-মুলে= p money

So, = P= C +Crt / 100

Or, P= C (1+rt/100)

If you remember this formula, it is possible to solve all mathematical problems.

Question: how many years will the capital be doubled at the rate of 5 taka per year?

Solution:

If you do it directly, time = (2) / 5 x 100 = 20 years

As a result of applying formula, = C (1 + 100)

Here, = 2 C, = 5, 2 (1 + 5) (1 + 5) (1 + 5 x / 100)

Or, 2= 1+ t/20, or, 1= t/20

Or, t= 20 yrs