Question

用简便方法计算：3.21+3.21x99

Answer 1

3.21+3.21x99 =3.21x(99+1) =3.21x100 =321

Answer 2

=3.21×（99+1）
=3.21×100
=321

Answer 3

=3.27×（100-1）
=3.27×100-1×3.27
=323.73

追答

正确答案（99+1）×3.27

Answer 4

提出3.21得3.21（1+99）＝3.21×100＝321

Answer 5