Deepak invested an amount of ₹ 21250 for 6 years. At what rate of simple interest will be obtain the total amount of ₹ 26350 at the end of 6 years?

### Concept & Simple Interest Rate Formula To find the rate of interest ($R$) when Principal ($P$), Final Amount ($A$), and Time ($T$) are given, we first calculate the Simple Interest ($SI = A - P$). The formula for the rate is: $$R = \frac{SI \times 100}{P \times T}$$ ### Step-by-Step Solution * Given Principal, $P = \text{₹ } 21250$ * Given Final Amount, $A = \text{₹ } 26350$ * Given Time, $T = 6 \text{ years}$ * First, determine the Simple Interest earned over 6 years: $SI = 26350 - 21250 = \text{₹ } 5100$ * Next, calculate the Rate: $R = \frac{5100 \times 100}{21250 \times 6}$ $R = \frac{510000}{127500} = 4\%$ p.a. ### Exam Strategy & Shortcut Instead of large multiplication, cancel out zeros and simplify step-by-step: $R = \frac{5100}{212.5 \times 6} = \frac{850}{212.5} = 4\%$. Since $4\%$ is not listed among the explicit options, select "None these". ### Common Pitfall A common mistake is assuming the given Amount ($26350$) is the Interest, which would yield an impossibly high rate. Always double-check what the values represent. ### Final Answer Therefore, the correct answer is **None these**.