英国数学教育家贝克浩斯(Backhousl100100
1 50140
1
2
3
2-=
130801020
2100401030
3802002060
4=
=2+2
2 35244.6
C
3A1A2
5B1B2
3A1=A25B1=B2
A2B23A1+5B1
241212
24-1212
1681812.4108
238100506040
3 2450140
13020
4 5042140
5 204050140
3020
15