Arithmetic aptitude :: Simple Interest :: General Questions

• Simple Interest - General Questions
• Simple Interest - Data Sufficiency 1
• Simple Interest - Data Sufficiency 2
• Simple Interest - Important Formulas and Facts

Principal :

The amount of money one borrows from a lender for a certain period of time is known as principal amount or the sum.

Interest :

Extra charge paid for the borrowed money is called Interest

Simple Interest (S.I.) :

Simple interest is a method to calculate the interest amount on a loan

Let Pricipal $=P$, Rate $=R\%$ per annum (p.a.) and Time $=N$ years. Then

(i) Simple interest (SI) $=\left(\frac{P\times N\times R}{100}\right)$

(ii) $P$ $=\left(\frac{100\times SI}{R\times N}\right)$ ; $R=\left(\frac{100\times SI}{P\times N}\right)$ and $N=\left(\frac{100\times SI}{P\times R}\right)$.

Syam took a loan of Rs. 1400 with simple interest for as many years as the rate of interest. If he paid Rs. 864 as interest at the end of the loan period, what was the rate of interest ?

Answer:

Explanation:

Let rate $=A%$ and time $=A$ years.

Then, $\left(\frac{(1400\times A\times A)}{100}\right)$ $=864$

$\Rightarrow 14A^{2}$ $=864$ $\Rightarrow A^{2}$ $=36$

$A$ = 6

A sum fetched a total simple interest of Rs. 5025 at the rate of 10 p.c.p.a. in 7 years. What is the sum ?

Answer:

Explanation:

Principal Rs $=\frac{(100\times 5025)}{(7\times 6)}$

$=\frac{502500}{70}$

= Rs. 7178.57

Mr. Abhishek invested an amount of Rs. 14,900 divided in two different schemes A and B at the simple interest rate of 16% p.a. and 13% p.a. respectively. If the total amount of simple interest earned in 3 years be Rs. 6261, what was the amount invested in Scheme B ?

Answer:

Explanation:

Let the sum invested in Scheme $A$ be Rs. $x$ and that in Scheme $B$ be Rs. $(14900-x)$

$\left(\frac{(x\times 16\times 3)}{100}\right)$ $+\left(\frac{((14900-x)\times 13\times 3)}{100}\right)$ $=6261$

$\Rightarrow 48x-39x$ $=626100-(14900\times 39)$

$\Rightarrow 9x$ $=45000$

$\Rightarrow x$ $=5000$

So, sum invested in Scheme $B$ = Rs. $(14900-5000)$ = Rs. 9900

A sum of money at simple interest amounts to Rs. 900 in 3 years and to Rs. 954 in 4 years. The sum is:

Answer:

Explanation:

$SI$ for $1$ year = Rs. $(954-900)$ = Rs. $54$.

$SI$ for $3$ years = Rs. $(54\times 3)$ = Rs. $162$.

So the Principal = Rs. $(954-162)$ = Rs. 792.

• Simple Interest - General Questions
• Simple Interest - Data Sufficiency 1
• Simple Interest - Data Sufficiency 2