答案
333x21+999x93
=333x3x7+999x93
=999x7+999x93
=999x(7+93)
=999x100
=99900
333x21+999x93
=333x3x7+999x93
=999x7+999x93
=999x(7+93)
=999x100
=99900
333×21+999×93
=333×21+333×3×93
=333×(21+279)
=333×300
=99900
333×21+999×93
=333×3×7+999×93
=(333×3)×7+999×93
=999×7+999×93
=999×(93+7)
=999×100
=99900