压路机问题：压路机的滚筒是一个圆柱，它的宽为2米，半径为0.5米，压路机向前滚动100周，压过的路面有多大？

本题由资优网老师数学题解答：压路机的滚筒是圆柱形，滚筒与地面相接触的是它的侧面，所以算压过的路面有多大，需要先算出圆柱的侧面积，再乘100（因为它滚了100周，所以是侧面积的100倍）。

滚筒的侧面积＝底面周长×高，算式如下：

3.14×0.5×2　×　2　＝　6.28（平方米）

压过的路面面积：

6.28×100＝628（平方米）

答：压过的路面的面积是628平方米。

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