The cost of setting up the type of a magazine is Rs. 1000. The cost of running the printing machine is Rs. 120 per 100 copies. The cost of paper, ink and so on is 60 paise per copy. The magazines are sold at Rs. 2.75 each. 900 copies are printed, but only 784 copies are sold. What is the sum to be obtained from advertisements to give a profit of 10% on the cost?

Options

A. Rs. 730
B. Rs. 720
C. Rs. 726
D. Rs. 736

Answer

To solve the problem step by step, we will calculate the total cost of producing the magazines, the revenue from selling the magazines, and finally determine the amount needed from advertisements to achieve a 10% profit.

### Step 1: Calculate the total cost of producing 900 copies.
1. **Fixed cost**: Rs. 1000 (cost of setting up the type).
2. **Variable cost for printing**: Rs. 120 per 100 copies. Therefore, for 900 copies:
\[ \text{Printing cost} = \left(\frac{900}{100}\right) \times 120 = 9 \times 120 = Rs. 1080 \]
3. **Cost of paper, ink, etc.**: Rs. 0.60 (60 paise) per copy. Therefore, for 900 copies:
\[ \text{Cost of paper, ink, etc.} = 900 \times 0.60 = Rs. 540 \]

4. **Total cost (CP)**:
\[ \text{Total cost} = \text{Fixed cost} + \text{Printing cost} + \text{Cost of paper, ink, etc.} \]
\[ \text{Total cost} = 1000 + 1080 + 540 = Rs. 2620 \]

### Step 2: Calculate the revenue from selling 784 copies.
1. **Selling price per magazine**: Rs. 2.75
2. **Total revenue from selling 784 copies**:
\[ \text{Revenue} = 784 \times 2.75 = Rs. 2156 \]

### Step 3: Calculate the loss incurred.
1. **Loss**:
\[ \text{Loss} = \text{Total cost} - \text{Revenue} \]
\[ \text{Loss} = 2620 - 2156 = Rs. 464 \]

### Step 4: Calculate the desired profit.
1. **Desired profit**: 10% of the total cost.
\[ \text{Desired profit} = 0.10 \times 2620 = Rs. 262 \]

### Step 5: Calculate the total amount needed to achieve the desired profit.
1. **Total amount needed**:
\[ \text{Total amount needed} = \text{Loss} + \text{Desired profit} \]
\[ \text{Total amount needed} = 464 + 262 = Rs. 726 \]

### Conclusion:
The sum to be obtained from advertisements to give a profit of 10% on the cost is **Rs. 726**.

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