Given the rationale, provide a reasonable question and answer. Step-by-step reasoning process: The wheelbarrow cost $30 because 60 / 2 = 30. The farmer earned $60 from selling fowl because 30 / (1 / 2) = 60. The farmer earned $40 selling chickens because 5 x 8 = 40. The farmer earned $20 selling ducks because 60 - 40 = 20. The farmer sold 2 ducks because 20 / 10 = 2.
The question and answer:
A farmer is selling ducks and chickens at the market. He sells ducks for $10 and chickens for $8. He sells 5 chickens and some ducks. He then spends half his earnings on a new wheelbarrow. After buying it, someone sees it and agrees to pay the farmer double what the farmer paid and the farmer earns another $60. How many ducks did the farmer sell?
The answer is 2