Final answer:
The firm's economic profit is $3 million, calculated by subtracting the implicit cost of $7 million from the accounting profits of $10 million.
Step-by-step explanation:
If accounting profits equal $10 million for a firm and the owners could likely earn $7 million in a similar business, the firm's economic profit is $3 million.
To calculate economic profit, you need to subtract both the explicit and implicit costs (opportunity costs of the next best alternative) from the total revenues. In this case, the accounting profit represents total revenues minus explicit costs, while the $7 million represents the implicit cost, being the earnings the owners could have made if they invested their time, energy, and resources in a similar business.
Therefore, the economic profit calculation would be:
Accounting profit - Implicit costs = $10 million - $7 million = $3 million.