Rs 775, invested for 8 years an interest of Rs 434. The rate of simple interest per annum is :

Options

A. `8%`
B. `7.5 %`
C. `7%`
D. `9%`

Answer

To find the rate of simple interest per annum, we can use the formula for Simple Interest (SI):

\[ SI = \frac{P \times R \times T}{100} \]

Where:
- \(SI\) = Simple Interest
- \(P\) = Principal amount (initial investment)
- \(R\) = Rate of interest per annum
- \(T\) = Time in years

Given:
- \(SI = 434\)
- \(P = 775\)
- \(T = 8\)

We need to find \(R\).

### Step 1: Substitute the known values into the formula

\[ 434 = \frac{775 \times R \times 8}{100} \]

### Step 2: Simplify the equation

Multiply both sides by 100 to eliminate the fraction:

\[ 43400 = 775 \times R \times 8 \]

### Step 3: Calculate \(775 \times 8\)

\[ 775 \times 8 = 6200 \]

### Step 4: Substitute back into the equation

Now we have:

\[ 43400 = 6200 \times R \]

### Step 5: Solve for \(R\)

Divide both sides by 6200:

\[ R = \frac{43400}{6200} \]

### Step 6: Perform the division

\[ R = 7 \]

### Conclusion

The rate of simple interest per annum is \(7\%\).

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