1.49+499+4999+49999+499999;2.(1+11+21+31+41)+(9+19+29+39+49)
来源:学生作业帮 编辑:作业帮 分类:数学作业 时间:2024/08/24 14:11:54
1.49+499+4999+49999+499999;2.(1+11+21+31+41)+(9+19+29+39+49)
1.49+499+4999+49999+499999; 2.(1+11+21+31+41)+(9+19+29+39+49) 3.(9999+9997+1995+……+9001)-(1+3+5+……+999 ) 4.123+234+345+456+5657+678+789 5.1400÷25÷8+350÷4÷125 6.9÷13+13÷9+11÷13+14÷9+6÷13
6.(0.36×5.1×81)÷(0.17×8.1×0.4)
六道都要写
1.49+499+4999+49999+499999; 2.(1+11+21+31+41)+(9+19+29+39+49) 3.(9999+9997+1995+……+9001)-(1+3+5+……+999 ) 4.123+234+345+456+5657+678+789 5.1400÷25÷8+350÷4÷125 6.9÷13+13÷9+11÷13+14÷9+6÷13
6.(0.36×5.1×81)÷(0.17×8.1×0.4)
六道都要写
1.49+499+4999+49999+499999;
=50+500+5000+50000+500000-5
=555550-5
=555545
2.(1+11+21+31+41)+(9+19+29+39+49)
=(1+9)+(11+19)+21+29)+(31+39)+(41+49)
=10+30+50+70+90
=50×5
=250
=50+500+5000+50000+500000-5
=555550-5
=555545
2.(1+11+21+31+41)+(9+19+29+39+49)
=(1+9)+(11+19)+21+29)+(31+39)+(41+49)
=10+30+50+70+90
=50×5
=250
1.49+499+4999+49999+499999;2.(1+11+21+31+41)+(9+19+29+39+49)
(1+11+21+31+41+51+1+71+81+91)+(9+19+29+39+49+59+69+79+89+99)
1+3+5+7+9+11+13+15+17+19+21+25+27+29+31+35+37+39+41+43+47+49
11*19+21*29+31*39+41*49+51*59+61*69+71*79+81*89+91*99 = 3308
数列1,3+5+7,9+11+13+15+17,19+21+23+…+29+31,…的第20项的和为( ).
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 57 49 41 43
那1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 4
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43
1-3+5-7+9-11+13-15+17-19+21-23+25-27+29-31+33-35+37-39+41=?
1+3+5+7+9+11+13+15+17+19+21+23+25+27+29+31+33+35+37+39+41+43
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 37 39 41 …… 其中
(1/11+1/21+1/31+1/41)*(1/21+1/31+1/41+1/51)-(1/11+1/21+1/31+