《应用加法运算律进行简便计算》ppt课件(四年级下册数学)
《应用加法运算律进行简便计算》ppt课件(四年级下册数学)第3页

=127+300+2

=427+2

=429

=354+100+3

=454+3

=457

=(89+11)+125

=100+125

=225

=238+400+2

=638+2

=640

=417+300+5

=717+5

=722

=257+(35+65)

=257+100

=357