Calculation of Compound Interest for Vijay's deposit:

Given: Principal amount (P) = Rs. 120000, Rate of Interest (R) = 15%, Time period (T) = 3 years

Formula: Compound Interest (CI) = P * [ (1 + R/100)^T - 1 ]

Step-by-Step Calculation:
- Firstly, we need to calculate the amount (A) that Vijay will get after 3 years at a simple interest rate of 15% per annum. The formula for simple interest is:
Simple Interest (SI) = (P * R * T)/100
Substituting the given values, we get:
SI = (120000 * 15 * 3)/100 = Rs. 54000
Hence, Vijay will get Rs. 54000 as simple interest after 3 years.

- Now, we need to calculate the compound interest (CI) that Vijay will get after 3 years. The formula for compound interest is given above. Substituting the given values, we get:
CI = 120000 * [ (1 + 15/100)^3 - 1 ]
= 120000 * (1.15^3 - 1)
= Rs. 58719.75
Hence, Vijay will get Rs. 58719.75 as compound interest after 3 years.

- Finally, we can calculate the total amount (T) that Vijay will get after 3 years. The formula for total amount is:
Total Amount (T) = Principal + Simple Interest + Compound Interest
Substituting the given values, we get:
T = 120000 + 54000 + 58719.75
= Rs. 232719.75
Hence, Vijay will get a total amount of Rs. 232719.75 after 3 years.

Conclusion:
Vijay deposited Rs. 120000 for 3 years at an interest rate of 15% per annum. He will get Rs. 54000 as simple interest, Rs. 58719.75 as compound interest, and a total amount of Rs. 232719.75 after 3 years.

Here, the P = Rs 120000