Question

find the sum to be invested to earn a simple interest of RS.360 in 8 months at the rate of 15% per annum ​

Answer 1

• Sum to be invested is Rs.3600 .

Step-by-step explanation:

To find:-

• Sum to be invested.

Solution:-

Given that,

S.I or simple interest is Rs 360

Time period is 8 months.

Rate of interest is 15%.

Conversion:-

Time = 8 months

= 8/12 = 4/6 = 2/3

Total time is 2/3 years.

• Sum to be invested means Principal or principal is denoted by P.

Simple interest = Principal × Rate × time

➝ 360 = P × 15 × 2/100 × 3

➝ 360 = P × 30/300

➝ 360 × 300 = P × 30

➝ 108000 = P × 30

➝ 108000/30 = P

➝ 3600 = P

Or, ➝ P = 3600.

Therefore,

Sum to be invested is Rs.3600 .

Answer 2

Given :

• SI = RS.360

• Time = 8 months = 2/3

• Rate = 15% per annum

To Find :

• find the sum to be invested

Solution :

Concept :

Simple interest is a quick and easy method of calculating the interest charge on a loan.

• Use this simple interest calculator to find A, the Final Investment Value, using the simple interest formula: A = P(1 + rt)

• where P is the Principal amount of money to be invested at an Interest Rate R% per period for t Number of Time Periods.

Where r is in decimal form; r=R/100; r and t are in the same units of time.

S I = ( p × R × T ) / 100

Substitute all values :

➫ 360 = ( P × 15 × 2 ) / 100 × 3

➫ 360 = 30P / 300

➫ P = 360 × 300 / 30

➫ P = 360 × 10

➫ P = 3600 Rs

• Hence the principal amount. 3600 ₹