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+31+32+33+34+35+36+37+38+39+40+41+42+43+44+45+46+47+48+49+50=?
Tính:
10 + 20 + 40 = … | 70 – 20 – 10 = … | 80 – 50 – 20 = … |
30 + 10 + 50 = … | 70 – 10 – 20 = … | 20 + 40 – 60 = … |
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+31+32+33+34+35+36+37=
Tính nhẩm:
40 + 10 = … | 30 + 40 = … | 50 + 30 = … |
30 + 30 = … | 60 + 20 = … | 30 + 50 = … |
20 + 50 = … | 10 + 80 = … | 40 + 20 = … |
Tính nhẩm:
a)
60 + 20 = 80 - 20 = 40 + 50 =
70 + 10 = 90 - 10 = 90 - 40 =
50 + 30 = 70 - 50 = 90 - 50 =
20+30+10=??
50+30=???
50-50=???
70+20+10=???
Điền dấu <, >, = thích hợp vào chỗ chấm:
50 - 10 ...20 40 - 10....40 30....50 - 20
1+2+3+4+5+6+7+8+9=
10+20+39+40+50+60+70+80+90=
11+22+33+44+55+66+77+88+99=
Tkk cho đừng quên kb nha hjjjj
Tính nhẩm :
20 + 30 = ?
Vậy 20 + 30 = 50
50 + 10 = 40 + 30 = 50 + 40 =
20 + 20 = 20 + 60 = 40 + 50 =
30 + 50 = 70 + 20 = 20 + 70 =