A rectangular playground. On the scale of 1 / 1000, the playground is 7 cm long and 4 cm wide. The actual area of the playground is ()

A rectangular playground. On the scale of 1 / 1000, the playground is 7 cm long and 4 cm wide. The actual area of the playground is ()

I'll answer
If the scale is 1000 to 1, its actual length is 7000 cm, that is 70 meters, and its width is 40 meters. Then its area is 280 square meters