A fruit-seller sells 4 oranges for 3, gaining 50%. Find :
C.P. of 4 oranges.

Answer

To find the cost price (C.P.) of 4 oranges when a fruit-seller sells them for 3 rupees and gains 50%, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Selling Price (S.P.) of 4 Oranges:**
The fruit-seller sells 4 oranges for 3 rupees.
\[ \text{S.P. of 4 oranges} = 3 \text{ rupees} \]

2. **Calculate the Selling Price (S.P.) of 1 Orange:**
To find the selling price of one orange, divide the total selling price by the number of oranges.
\[ \text{S.P. of 1 orange} = \frac{3}{4} \text{ rupees} \]

3. **Understand the Gain Percentage:**
The gain is given as 50%. This means that the selling price is 150% of the cost price (C.P.).
\[ \text{Gain} = 50\% \]
Therefore,
\[ \text{S.P.} = \text{C.P.} \times \left(1 + \frac{\text{Gain}}{100}\right) = \text{C.P.} \times \left(1 + \frac{50}{100}\right) = \text{C.P.} \times \frac{150}{100} = \text{C.P.} \times 1.5 \]

4. **Set Up the Equation:**
Now, we can set up the equation using the selling price of 1 orange:
\[ \frac{3}{4} = \text{C.P.} \times 1.5 \]

5. **Solve for C.P.:**
To find the cost price (C.P.), rearrange the equation:
\[ \text{C.P.} = \frac{3/4}{1.5} \]
Convert 1.5 to a fraction:
\[ 1.5 = \frac{3}{2} \]
Now, substitute this into the equation:
\[ \text{C.P.} = \frac{3/4}{3/2} = \frac{3}{4} \times \frac{2}{3} = \frac{2}{4} = \frac{1}{2} \text{ rupees} \]

6. **Find C.P. of 4 Oranges:**
Since we need the cost price of 4 oranges:
\[ \text{C.P. of 4 oranges} = \text{C.P. of 1 orange} \times 4 = \frac{1}{2} \times 4 = 2 \text{ rupees} \]

### Final Answer:
The cost price of 4 oranges is **2 rupees**.