1、52.7d0.41.6c87.924用圆规画一个半径是2cm的圆,并求出它的周长。5一只挂钟的分针长20cm,经过120分钟后,分针尖端所走的路程是多少厘米?6一个圆的周长是40.82cm,它的半径是多少厘米?(1)r=0.8cm(2)d=6.4cm(3)d=0.5cm10cm7.4cm97.31.21.77131.884用圆规画一个直径是3.2cm的圆,并求出它的周长。5一只挂钟的分针长60cm,经过15分钟后,分针尖端所走的路程是多少厘米?6一个圆的周长是28.26cm,它的直径是多少厘米?(1)d=2cm(2)r=5.6cm(3)d=2.5cm19cm9.4cm146.11.31.475
2、6.525一只挂钟的分针长30cm,经过120分钟后,分针尖端所走的路程是多少厘米?(1)d=2.8cm(2)d=7.2cm(3)r=3cm13cm5.6cm104.321.78122.464用圆规画一个直径是2cm的圆,并求出它的周长。5一只挂钟的分针长10cm,经过60分钟后,分针尖端所走的路程是多少厘米?6一个圆的周长是9.42cm,它的直径是多少厘米?(1)r=3.2cm(2)r=1.6cm14cm5.2cm3.411.09106.764用圆规画一个半径是1.2cm的圆,并求出它的周长。5一只挂钟的分针长20cm,经过10分钟后,分针尖端所走的路程是多少厘米?6一个圆的周长是43.96
3、cm,它的半径是多少厘米?(1)r=1.2cm(2)r=4cm(3)r=0.5cm8cm6.6cm85.60.31.745一只挂钟的分针长30cm,经过35分钟后,分针尖端所走的路程是多少厘米?6一个圆的周长是69.08cm,它的直径是多少厘米?(2)r=6.4cm(3)r=3.5cm3cm1.4cm201.51.71.6125.124用圆规画一个直径是2.8cm的圆,并求出它的周长。5一只挂钟的分针长30cm,经过10分钟后,分针尖端所走的路程是多少厘米?6一个圆的周长是65.94cm,它的直径是多少厘米?(1)d=1.6cm(2)d=5.6cm7.8cm34.11.5531.44用圆规画一个直径是1.6cm的圆,并求出它的周长。5一只挂钟的分针长50cm,经过85分钟后,分针尖端所走的路程是多少厘米?6一个圆的周长是3.14cm,它的半径是多少厘米?(1)d=1.2cm20cm2.294.25一只挂钟的分针长40cm,经过40分钟后,分针尖端所走的路程是多少厘米?6一个圆的周长是47.1cm,它的半径是多少厘米?(1)d=2.4cm(2)d=2.4cm12cm2cm41.91.9697.345一只挂钟的分针长40cm,经过50分钟后,分针尖端所走的路程是多少厘米?6一个圆的周长是9.42cm,它的半径是多少厘米?