The difference between the compound interest and the simple interest on a principal sum of $₹24,000$ in $2$ years at same rate of interest is $₹60$. The rate of interest is:
To find the rate of interest at which the difference between the compound interest (CI) and simple interest (SI) for a principal of ₹24,000 over 2 years is ₹60, we need to use the formula for the difference between CI and SI. The difference over 2 years is given by:
\(CI - SI = \frac{P \cdot R^{2}}{100^{2}}\)
Here, \(CI - SI = ₹60\), \(P = ₹24,000\), and \(R\) is the rate of interest in percentage that we need to find.
Substitute the known values into the formula:
\(60 = \frac{24000 \cdot R^{2}}{100^{2}}\)
Which simplifies to:
\(60 = \frac{24000 \cdot R^{2}}{10000}\)
By multiplying both sides by 10000 to clear the fraction, we get:
\(60 \times 10000 = 24000 \cdot R^{2}\)
\(600000 = 24000 \cdot R^{2}\)
Now, divide both sides by 24000 to solve for \(R^{2}\):
\(R^{2} = \frac{600000}{24000}\)
\(R^{2} = 25\)
Taking the square root of both sides, we find \(R\):
\(R = \sqrt{25} = 5\%\)
Thus, the rate of interest is 5%.
Conclusion: The correct answer is \(5\%\).
Find the interest (in ₹) on ₹8,000 at 10% per annum compounded half yearly for $1\frac{1}{2}$ years.
Amit had invested same amount of sums at simple as well as compound interest, compounded annually. The time period of investment for both the sums was 2 years and rate of interest too was the same, 4% per annum. At the end, he found a difference of ₹43 in both the interests received. What were the sums (in ₹) invested?
When the difference between compound interest, compounded annually, and simple interest for three years is ₹186 at 10% interest per annum, the principal is ₹______.