将图形A按1:2的比缩小画在方格纸上,变成图形B.(图中每小格的边长代表1厘米)(1)图A的面积SA= cm2;图B的面积SB= cm2;(2)﹣)
=15÷ =.
3÷ ==0.375= :24=24: .
=2.5:( )=125%=20÷( )=.
5: ==0.25= %
2.5÷ ==15: = %= (小数)