Question

00
Est
साधारण ब्याजदर पत्ता लगाउनुहोस् । (If Rs. 20000
amount to Rs. 21200 in 6 months find the rate of
simple interest.)
Ans: 12% n
Mc

Answer 1

Certainly! To find the simple interest rate when Rs. 20000 amounts to Rs. 21200 in 6 months, we can follow these steps:

### Step 1: Identify the Given Values
- Principal (P): Rs. 20000
- Amount (A): Rs. 21200
- Time (T): 6 months, which we need to convert into years

### Step 2: Calculate the Interest Earned
The interest earned ($\( I \)$) is the difference between the amount and the principal.
$\[ I = A - P \]$
$\[ I = 21200 - 20000 \]$
$\[ I = 1200 \, \text{Rs} \]$

### Step 3: Convert Time into Years
Since the time is given in months, and interest rates are typically calculated per annum (year), we need to convert 6 months into years.
$\[ T = \frac{6}{12} \]$
$\[ T = 0.5 \, \text{years} \]$

### Step 4: Use the Simple Interest Formula to Find the Rate
The formula for simple interest is:
$\[ I = P \times R \times T \]$
where $\( R \)$ is the rate of interest per annum.

Rearranging the formula to solve for $\( R \)$:
$\[ R = \frac{I}{P \times T} \]$

We already have:
- $\( I = 1200 \, \text{Rs} \)$
- $\( P = 20000 \, \text{Rs} \)$
- $\( T = 0.5 \, \text{years} \)$

Substituting these values into the formula:
$\[ R = \frac{1200}{20000 \times 0.5} \]$
$\[ R = \frac{1200}{10000} \]$
$\[ R = 0.12 \]$

To express $\( R \)$ as a percentage, we multiply by 100:
$\[ R = 0.12 \times 100 \]$
$\[ R = 12\% \]$

### Step 5: Conclusion
The rate of simple interest is:
$\[ \boxed{12\%} \]$