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题目:一个长方形的周长是30厘米,长是宽的2倍,求这个长方形的面积。小超看了看上面的题目,说:“这是一道求长方形面积的题,应先求出长和宽。已知这个长方形的周长是30厘米,且长是宽的2倍,把宽当作1份,那么长就是2份,因此,长方形的周长30厘米,相当于3份宽,既然3份宽是30厘米,所以可把宽先求出来:30÷(2+1)=10(厘米)。”长是宽的2倍,所以长是10×2=20(厘米),也可用周长30
Title: A rectangular perimeter is 30 cm long is 2 times the width of the rectangular area. Small super looked at the topic above, said: This is a rectangular area of the problem, you should first find the length and width of this rectangle is known to be 30 cm circumference, and the length is 2 times the width of the Therefore, the circumference of the rectangle is 30 centimeters, which is equal to 3 wide. Since the width of 3 is 30 centimeters, we can get the width first: 30 ÷ (2 + 1) = 10 (centimeters). "The length is twice as long, so the length is 10 × 2 = 20 (centimeters), and the perimeter 30