Find compound interest on Rs. 7500 at 4% per annum for 2 years, compounded annually

Answer: Option B

Explanation:

$$\begin{aligned} C.I. = (4000 \times(1+\frac{10}{100})^2 - 4000) \\ = 4000 * \frac{11}{10} * \frac{11}{10} - 4000 \\ = 840 \\ \text{So S.I. = } \frac{840}{2} = 420\\ \text{So Sum = } \frac{S.I. * 100}{R*T} \\ = \frac{420 * 100}{3*8} \\ = Rs 1750 \end{aligned}$$

Answer: Option D

Explanation:

Difference between C.I and S.I for 2 years = 36.30
S.I. for one year = 330.
S.I. on Rs 330 for one year = 36.30

So R% = \frac{100*36.30}{330*1} = 11%

Answer: Option A

Explanation:

Let the amount Rs 100 for 1 year when compounded half yearly, n = 2, Rate = 6/2 = 3%

$$\begin{aligned} Amount = 100(1+\frac{3}{100})^2 = 106.09 \end{aligned}$$

Effective rate = (106.09 - 100)% = 6.09%

Answer: Option B

Explanation:

Let the Sum be P
$$\begin{aligned} S.I. = \frac{P*4*2}{100} = \frac{2P}{25}\\ C.I. = P(1+\frac{4}{100})^2 - P \\ = \frac{676P}{625} - P \\ = \frac{51P}{625} \\ \text{As, C.I. - S.I = 1}\\ => \frac{51P}{625} - \frac{2P}{25} = 1 \\ => \frac{51P - 50P}{625} = 1 \\ P = 625 \end{aligned}$$

Answer: Option D

Explanation:

Please apply the formula

$$\begin{aligned} Amount = P(1+\frac{R}{100})^n \\ \text{C.I. = Amount - P} \end{aligned}$$