28×5+2×3×35+21×20+14×40+8×62 55×66+66×77+77×88+88×99脱式计算

来源：学生作业帮助网 编辑：作业帮 时间：2024/05/07 05:04:47

28×5+2×3×35+21×20+14×40+8×62 55×66+66×77+77×88+88×99脱式计算
28×5+2×3×35+21×20+14×40+8×62 55×66+66×77+77×88+88×99
脱式计算

28×5+2×3×35+21×20+14×40+8×62 55×66+66×77+77×88+88×99脱式计算
28×5+2×4×35+21×20+14×40+8×62
=2×2×7×5+2×4×5×7+3×7×4×5+2×7×5×2×4+8×62
=2×2×7×5×（1+2+3+4）+496
=10×14×10+496
=1400+496
=1896
55×66+66×77+77×88+88×99
=11×5×11×6+11×6×11×7+11×7×11×8+11×8×11×9
=11×11×(5×6+6×7+7×8+8×9)
=121×(30+42+56+72)
=121×200
=24200

楼上~ 有点小问题
28×5+2×3×35+21×20+14×40+8×62
=28×5+6×35+21×20+14×40+8×62
=140+210+210+560+496
=1826
55×66+66×77+77×88+88×99
=11×5×11×6+11×6×11×7+11×7×11×8+11×8×11×9
=11×11×(5×6+6×7+7×8+8×9)
=121×(30+42+56+72)
=121×200
=24200

3/2+3/4+4/5+5/14+4/21+3/28+2/35-3/7=简算打错了。应该是：2/3+3/4+4/5+5/14+4/21+3/28+2/35-3/7=简算 28×5+2×3×35+21×20+14×40+8×62 55×66+66×77+77×88+88×99脱式计算 1=7,2=14,3=21,4=28,5=35,6=42,7=? 谁帮我算下均数±标准差第一组：年龄：21,22,27,28,16,16,15,16,16,15,16,17,17,12,10,16,4,15,19,16,61,4,14,14,9,5,2,9,4,55,14,38,11,3,3,10,32,22,22,33,23,27,21,15,5,38,37,6,22,31,35,52,25,14,20,17,14,14,16,52,5,35,16,15,32,28,15第二组 帮我算下均值±标准差第一组：年龄：21,22,27,28,16,16,15,16,16,15,16,17,17,12,10,16,4,15,19,16,61,4,14,14,9,5,2,9,4,55,14,38,11,3,3,10,32,22,22,33,23,27,21,15,5,38,37,6,22,31,35,52,25,14,20,17,14,14,16,52,5,35,16,15,32,28,15,平均年 1*2*3*3*6*9+5*10*15+7*14*21/(2*3*4+6*9*12+10*15*20+14*21*28) 14*5**8*7 ***71*5*2 95*2****4 *21***35* ***3*2*** *69***27* 2****1*83 7*6*28*** 8*4**3*26 * | 1 2 3 4 5 6 7 8 9-------------------------------1 | 1 2 3 4 5 6 7 8 92 | 2 4 6 8 10 12 14 16 183 | 3 6 9 12 15 18 21 24 274 | 4 8 12 16 20 24 28 32 365 | 5 10 15 20 25 30 35 40 456 | 6 12 18 24 30 36 42 48 547 | 7 14 21 28 35 42 49 56 638 | 8 16 1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+24+26+27+28+29+30+31=32+33+34+35=? 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= 1 2 5 10 17 26 4 3 6 11 18 27 9 8 7 12 19 28 16 15 14 13 20 29 25 24 23 22 21 30 36 35 34 33 32 31是个什么数列? 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=? 1+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=? 1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+117+18+19+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36=几 1+2+3+4+5+6+7+8+9+10+11+121+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+= 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 用十 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=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+37039+40= （1*3*5+2*6*10+7*21*35）/（3*4*5+6*8*10+21*28*35）