基础强化
1、半径=0.6÷2=0.3
体积=3.14x0.3²x3
=3.14x0.09x3
=0.8478
2、半径=2÷2=1
体积=3.14x1²x12x1/3x4
=3.14x1x12x1/3x4
=50.24
3、半径=0.6÷2=0.3
体积=3.14x0.3²x1
=3.14x0.09x1
=0.2826
次数=50.24÷0.2826≈176 (用舍去法)
拓展应用
4、体积=3.14x10²x2
=3.14x100x2
=628
5、用铁皮
3.14x12²+3.14x12x2x35
=3.14x144+3.14x12x2x35
=452.16+2637.6
=3089.76
盛水
3.14x12x35
=3.14x144x35
=15825.6
自我挑战
6、半径=18x2÷6÷2=3
底面积=3.14x3²
=3.14x9
=28.26
体积=28.26x6÷3=56.52