Final answer:
To find the percentage of land available for farming, divide the number of acres available for farming by the total number of acres owned by the Santos family, and multiply by 100. In this case, about 66.67% of the land is available for farming.
Step-by-step explanation:
To find the percentage of land available for farming, we need to divide the number of acres available for farming by the total number of acres owned by the Santos family, and then multiply by 100. In this case, the Santos family owns 30 acres, but only 20 acres can be farmed. So, the percentage of land available for farming is:
(20/30) * 100 = 66.67%
Therefore, about 66.67% of the land is available for farming.