Các câu hỏi tương tự
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+28+29+30=
1 × 2 + 2 × 3 +3 × 4 + 4 × 5 + 5 × 6 + 6 × 7 + 7 × 8 + 8 × 9 + 9 × 10 + 10 × 11 +11 ×12 + 12 ×13 + 13×14 + 14×15 + 15×16 + 16×17 +17×18 + 18×19 + 19×20 + 20×21 + 21×22 + 22×23 + 23×24 + 24×25 + 25×26
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+149+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37+38+39*100
Tính nhanh
a) 3/5 + 6/11 + 7/13 + 2/5 + 16/11 + 19/13 =
b) 1995/1997 + 1990/1993 + 1997/1994 + 1993/1995 + 997/995
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20=?
Tính nhanh
1×2×3×4×5×6×7×8×9×10×11×12×13×14×15×16×17×18×19×20
1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10
2 + 4 + 6 + 8 + 10 + 12 + 14 + 16 + 18 + 20
1 + 3 + 5 + 7 + 9 + 11 + 13 + 15 + 17 + 19
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20
1+2+3-4+5+6-7+8+9-10+11+12-13+14+15-16+17+18-19+20:15x2