A-A+
计算 写出必要过程.92:x=247:0.5259+3910-5.22259-62750+5
问题详情
计算,写出必要过程.
2008×98
1+2-3+4+5-6+7+8-9+…+601+602-603+604+605-606.
参考答案
①92:x=247:0.5,
247x=92×0.5,
247x=94,
x=78;
②259+3910-5.22259-62750+5.22÷(2006×0.42008×0.5+1.62008),
=259-1.32259-1.32÷1606.42008,
=2008016064,
=12551004;
③2008×9814-225×10125+20045×2834,
=2008×3934-225×25125+10045×1154,
=197286-2259+5773,
=200800;
④1+2-3+4+5-6+7+8-9+..+601+602-603+604+605-606,
=(1+2-3)+(4+5-6)+(7+8-9)+…(604+605-606),
=0+3+6+9+…+603,
=(0+603)×202÷2,
=60903.
考点:过程