Explanation:

Let's solve the problem:

- Principal amount (P) = Rs. 10,000

- Total amount received by Sachin after 4 years is Rs. 15,000 (Rs. 10,000 + Rs. 5,000)

- SI = Total amount - Principal = Rs. 15,000 - Rs. 10,000 = Rs. 5,000

- Time (T) = 4 years

The formula for Simple Interest (SI) is:

$$\text{SI}=\frac{P\times R\times T}{100}$$

- Plugging in the values:

$$5000=\frac{10000\times R\times 4}{100}$$

$$5000=400R$$

$$R=\frac{5000}{400}=12.5\mathrm{\%}$$

- Answer (Option 1: 12.5%):