Explanation:

Let's solve the problem step by step:

- Given that the sum of money becomes $\frac{11}{8}$ times itself, this means that the interest earned makes the total amount $\frac{11}{8}$ of the principal.

- In simple interest, Total Amount (A) = Principal (P) + Interest (I).

- Interest (I) = Principal (P) × Rate (R) × Time (T) / 100.

- Given Rate (R) = 6.25% and Total Amount = $\frac{11}{8}$ times Principal.

From the basic formula:

$$\frac{11}{8}P=P+\frac{P\times 6.25\times n}{100}$$

To find 'n', we simplify the equation:

$$\frac{3}{8}P=\frac{6.25Pn}{100}$$

Divide both sides by P and solve for n:

$$\frac{3}{8}=\frac{6.25n}{100}$$

$$n=\frac{3\times 100}{8\times 6.25}=\frac{300}{50}=6$$

- Option 1: 6

- Option 2: 8

- Option 3: 5

- Option 4: 7

- ?? Correct Answer: Option 1: 6

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