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【例2】一个正方形被分成4个大小、形状完全一样的长方形,每个小长方形的周长都是75厘米,求这个正方形的周长。【解析】根据已知条件,可以算出4个长方形周长的和是75×4=300(厘米)。观察上图,发现4个长方形的周长和等于8条长与8条宽的长度和。因为是4个长方形拼成了一个正方形,可见正方形的边长=长方形的长=长方形的宽×48条长方形的长+8条长方形的宽=8条正方形的边长+2条正方形的边长
Example 2 A square is divided into four rectangles of exactly the same size and shape. Each small rectangle has a circumference of 75 cm. Find the circumference of the square. 【Explanation】 According to the known conditions, we can calculate the sum of four rectangular perimeter is 75 × 4 = 300 (cm). Observe the figure above and found the circumference of 4 rectangles and the length sum of 8 lengths and 8 widths. Because it is 4 rectangular spell into a square, we can see the length of the side of the rectangle = length of the rectangle = width of the rectangle × width of 48 rectangles + width of 8 rectangles = length of sides of 8 squares + length of sides of 2 squares