Correct Answer - Option 4 : Rs.6,821

**Given:**

Principal = Rs. 15,000

Rate% = 15% p.a compounded annually

Time = 2(2/3) years

**Formula used**:

Amount = P × (1 + r/100)^{2}(1 + 2r/300)

**Calculation:**

∵ Rate% for 2/3 years = 15% × (2/3)

= 10%

∴ Amount = P × (1 + r/100)2(1 + 2r/300)

= 15,000 × (1 + 15/100)^{2}(1 + 10/100)

= 15,000 × (1 + 3/20)2(11/10)

= 15,000 × (23/20)^{2}(11/10)

= (15000 × 529 × 11)/(400 × 10)

= Rs. 21,821.2

∴ CI = Amount - Principal

= 21,821.2 - 15,000

= Rs. 6821.2