Math problem in the third grade of primary school: the school should rebuild the playground with a circumference of 220 meters. If the area after reconstruction is the largest, what should it be?

Analysis: The known circumference is 220 meters. Because the square has the largest area, it is 220÷4=55 meters and 55×55=3025 square meters.

However, it needs to be rectangular. When the side length is 55 meters, you can add 1 meter and subtract 1 meter.

That is, 54 meters and 56 meters, so it is 54×56=3024 square meters, and the largest area after transformation is 3024 square meters.

The rice is also a rectangle, with 54 on one side and 56 on the other.

Column type;

Square: 220 ÷ 4 = 55 (meter) 55 × 55 = 3025 (square meter)

Rectangular: 54 × 56 = 3024 (square meter)

Because 3025 square meters > 3024 square meters, the square area is the largest.

A little plagiarism, please forgive me.