5+5+6+7+8+9-10-7-9+5+6-12
Tính nhẩm:
7 x 8 = ..... 16 : 2 = ..... 36 : 6 = ..... 49 : 7 = .....
2 x 5 = ..... 72 : 8 = ..... 9 x 3 = ...... 63 : 7 = .....
6 x 4 = ..... 25 : 5 = ..... 4 x 8 = ...... 7 x 5 = ......
45 x 6 =
1 + 1 + 2 + 2 + 3 + 3 + 4 + 4 + 5 + 5 + 6 + 6 + 7 + 7 + 8 + 8 + 9 + 9 =
78 : 5 =...(dư...)
45 : 5 =
x : 5 = 25
1+1+2+2+3+3+4+4+5+5+6+6+7+7+8+8+9+9+10+10=
1+1-2+2-3+3-4+4-5+5-6+6-7+7-8+8-9+9-10=?
10 . 10 =
9 . 9 =
8 . 8 =
7 . 7 =
6 . 6 =
5 . 5 =
4 . 4 =
3 . 3 =
2 . 2 =
1 . 1 =
7+8+5+7+8+9+7+10+6+8+9+12:2
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27=.................................
A= 5/9*7/13+5/9*6/13
B=(1/99+12/999+123/9999)*(1/2-1/3-1/6)
tính