The effective annual rate of interest corresponding to a nominal rate of 6% per annum payable half-yearly is
Aptitude
Compound Interest
Difficulty: Easy
Choose an option
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A6.06%
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B6.07%
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C6.08%
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D6.09%
Answer
Correct Answer: 6.09%
Explanation
### Concept & Effective Annual Rate (EAR)
When interest is compounded more than once a year, the effective annual rate (EAR) is higher than the nominal annual rate due to compounding.
$$EAR = \left(1 + \frac{R}{n \times 100}\right)^n - 1$$
### Step-by-Step Solution
1. **Identify the given values:**
Nominal annual rate = 6%
Compounding frequency = half-yearly ($n = 2$)
2. **Determine half-yearly rate:**
Rate per half-year = $\frac{6\%}{2} = 3\%$
3. **Calculate effective rate for two periods (1 year):**
Equivalent multiplier = $\left(1 + \frac{3}{100}\right)^2 = (1.03)^2$
$(1.03)^2 = 1.0609$
4. **Convert to percentage:**
Effective rate = $(1.0609 - 1) \times 100\% = 0.0609 \times 100\% = 6.09\%$
### Exam Strategy & Shortcut
Use the successive percentage formula for 2 periods: $A + B + \frac{A \times B}{100}$.
Here, $A = 3\%$, $B = 3\%$.
Effective Rate = $3 + 3 + \frac{3 \times 3}{100} = 6 + 0.09 = 6.09\%$.
### Common Pitfall
Misunderstanding "nominal rate". Some students mistakenly apply the 6% rate twice, yielding $6 + 6 + 0.36 = 12.36\%$, failing to divide the annual rate by the number of compounding periods first.
### Final Answer
Therefore, the correct answer is **6.09%**.