The correct answer is option (D):
115
Here's how to solve this problem, breaking it down step-by-step:
First, calculate the weighted average cost of the nuts. We're given the ratio of the nuts is 3:4:5. Let's assume the seller bought 3 kg of the first type, 4 kg of the second type, and 5 kg of the third type. This makes the total weight 3 + 4 + 5 = 12 kg.
Now, calculate the cost of each type of nut:
* Type 1: 3 kg * 100/kg = 300
* Type 2: 4 kg * 80/kg = 320
* Type 3: 5 kg * 60/kg = 300
Next, find the total cost of all the nuts: 300 + 320 + 300 = 920
Then, find the cost per kg of the mixture: 920 / 12 kg = 76.67/kg (approximately)
Finally, calculate the selling price with a 50% profit margin:
Profit per kg = 76.67 * 0.50 = 38.33
Selling price per kg = 76.67 + 38.33 = 115
Therefore, the seller sold the mixture at a price of 115/kg.