A fruit seller sold big, medium and small sized apples for Rs 15, Rs 10 and Rs 5 respectively. The total number of apples sold were in the ratio `3:2:5`. Find the average cost of an apple.

Options

A. 8
B. 10
C. 9
D. 7

Answer

To find the average cost of an apple sold by the fruit seller, we will follow these steps:

### Step 1: Define the ratio of apples sold
The ratio of big, medium, and small apples sold is given as 3:2:5. Let's denote:
- The number of big apples sold as \(3x\)
- The number of medium apples sold as \(2x\)
- The number of small apples sold as \(5x\)

### Step 2: Calculate the total number of apples sold
The total number of apples sold can be calculated by adding the parts of the ratio:
\[ \text{Total apples} = 3x + 2x + 5x = 10x \]

### Step 3: Calculate the total cost of each type of apple
Next, we calculate the total cost for each type of apple:
- Cost of big apples: \(3x \times 15 = 45x\)
- Cost of medium apples: \(2x \times 10 = 20x\)
- Cost of small apples: \(5x \times 5 = 25x\)

### Step 4: Calculate the total cost of all apples
Now, we can find the total cost of all the apples sold:
\[ \text{Total cost} = 45x + 20x + 25x = 90x \]

### Step 5: Calculate the average cost of an apple
The average cost of an apple can be calculated by dividing the total cost by the total number of apples:
\[ \text{Average cost} = \frac{\text{Total cost}}{\text{Total number of apples}} = \frac{90x}{10x} = 9 \]

Thus, the average cost of an apple is **Rs 9**.

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