This is a scale drawing of an actual park. What percent of the park is the picnic area?

To find the area of the picnic area on the map, we use the dimensions given:

The picnic area has dimensions of 10 inches by 10 inches.

To calculate the area, we use the formula for the area of a rectangle: \[ \text{Area} = \text{length} \times \text{width} \]

So, the area of the picnic area is: \[ \text{Area} = 10 , \text{in} \times 10 , \text{in} = 100 , \text{square in.} \]

Now, to find the percentage of the park that is the picnic area, we can use the formula: \[ \text{Percentage} = \left( \frac{\text{Area of picnic area}}{\text{Area of entire park}} \right) \times 100 \]

Substituting the values: \[ \text{Percentage} = \left( \frac{100 , \text{square in.}}{400 , \text{square in.}} \right) \times 100 = 25% \]

Therefore, the area of the picnic area is 100 square inches, and it constitutes 25% of the entire park.