49999+4999+499+49
=50000+5000+500+50-4
=55550-4
=55546
1+2+3+4.+35+36
=(1+36)×36÷2
=37×18
=666
好学的孩子
49999+4999+499+49 用简便计算怎么算?
49999+4999+499+49
=50000+5000+500+50-4
=55550-4
=55546
1+2+3+4.+35+36
=(1+36)×36÷2
=37×18
=666
好学的孩子