30+5=
14-6=
7+8=
12-5=
57-30=
16-9=
6+5=
17-8=
27+30=
47-30=
16+23=
26-14=
2×5=
4×5=
6×3=
6×5=
5×3=
3×3=
2×4=
4×3=
2×6-12=
5×3+8=
4×5-7=
5×5+5=
一共有多少个?
?
