Question

观察：4x6=24 14x16=224 24x26=624 34x36=1224 .

Answer 1

1、(10n+4)*(10n+6)

=100n*n+40n+60n+24

=100n(n+1)+24

2、124*126=100*12*13+24=15624

3、(10n+m)(10n+10-m)

=100n*n+10nm+100n+10m-10nm-m*m

=100n(n+1)+m(10-m)

32*38=1216

47*43=2021

81*89=7209