A tape-recorder is sold for 2,760 at a gain of 15% and a C.D. player is sold for Rs 3,240 at a loss of 10%. Find :
C.P. of the tape-recorder.

Answer

To find the cost price (C.P.) of the tape-recorder, we can use the formula that relates selling price (S.P.), cost price (C.P.), and gain percentage.

### Step-by-Step Solution:

1. **Identify the given values:**
- Selling Price (S.P.) of the tape-recorder = Rs 2760
- Gain percentage = 15%

2. **Use the formula for Cost Price:**
The formula to calculate the cost price when the selling price and gain percentage are known is:
\[ C.P. = \frac{100}{100 + \text{Gain Percentage}} \times \text{Selling Price} \]

3. **Substitute the values into the formula:**
\[ C.P. = \frac{100}{100 + 15} \times 2760 \]
\[ C.P. = \frac{100}{115} \times 2760 \]

4. **Simplify the fraction:**
\[ C.P. = \frac{100 \times 2760}{115} \]

5. **Calculate the multiplication:**
- First, calculate \(100 \times 2760 = 276000\).

6. **Now divide by 115:**
\[ C.P. = \frac{276000}{115} \]

7. **Perform the division:**
- \(276000 \div 115 = 2400\)

8. **Conclusion:**
The cost price of the tape-recorder is Rs 2400.

### Final Answer:
C.P. of the tape-recorder = Rs 2400