中学生网络课堂本课配套习题挑战模式1/5
单选题
难度系数：
1.甲、乙两种商品原来的单价和为100元. 因市场变化，甲商品降价10%，乙商品提价40%，调价后，两种商品的单价之和比原来的单价之和提高了20%. 求甲、乙两种商品原来的单价. 设甲商品原来的单价是x元，乙商品原来的单价是y元，根据题意可列方程组为（ ）
A:  |
B:  |
C:  |
D:  |
一次做对，真牛！
+5奖励规则>
- 提示1：IOagueaNruKAnOeUsuOAgeS5meS4pOenjeWVhuWTgeWOn+adpeeahOWNleS7t+WSjOS4ujEwMOWFg+KAneWPr+W+l+WHuuaWueeoi+S4ujxpbWcgd2lkdGg9NzIgaGVpZ2h0PTIxIHNyYz0iaHR0cHM6Ly9wMS5xaW5nZ3VvLmNvbS9HMS9NMDAvMjMvNDUvckJBQ0UxTU1VcjZnSUVPeEFBQUI2RXJhV1RRNzY3LnBuZyI+77yb
- 提示2：IOagueaNruKAnOeUsuWVhuWTgemZjeS7tzEwJe+8jOS5meWVhuWTgeaPkOS7tzQwJe+8jOiwg+S7t+WQju+8jOS4pOenjeWVhuWTgeeahOWNleS7t+S5i+WSjOavlOWOn+adpeeahOWNleS7t+S5i+WSjOaPkOmrmOS6hjIwJeKAne+8jOWPr+W+l+WHuuaWueeoi+S4ujxpbWcgd2lkdGg9MzIwIGhlaWdodD0yMSBzcmM9Imh0dHBzOi8vcDIucWluZ2d1by5jb20vRzEvTTAwLzAwLzU4L3JCQUNGRk1NVXI3eUxkaDNBQUFEcG5WNnhnTTkxMi5wbmciPg==
- 答案：Qw==
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
本课配套习题挑战模式2/5
单选题
难度系数：
2.
为了研究吸烟是否对肺癌有影响，某肿瘤研究所随机地抽查了10000人，并进行统计分析. 结果显示：在吸烟者中患肺癌的比例是2.5%，在不吸烟者中患肺 癌的比例是0.5%，吸烟者患肺癌的人数比不吸烟者患肺癌的人数多22人. 如果设这10000人中，吸烟者患肺癌的人数为x，不吸烟者患肺癌的人数为y， 根据题意，下面列出的方程组正确的是（ ）
| A:
|
| B:
|
| C:
|
| D:
|
一次做对，真牛！
+5奖励规则>
- 提示1：PHA+5qC55o2u4oCc5ZC454Of6ICF5oKj6IK655mM55qE5Lq65pWw5q+U5LiN5ZC454Of6ICF5oKj6IK655mM55qE5Lq65pWw5aSaMjLkurrigJ3lvpfliLDkuIDkuKrnrYnph4/lhbPns7s8L3A+
- 提示2：PHA+5qC55o2u4oCc5Zyo5ZC454Of6ICF5Lit5oKj6IK655mM55qE5q+U5L6L5pivMi41Je+8jOWcqOS4jeWQuOeDn+iAheS4reaCo+iCuueZjOeahOavlOS+i+aYrzAuNSXvvIzigJ3lvpfliLDnrKzkuozkuKrnrYnph4/lhbPns7s8L3A+
- 提示3：PHA+5qC55o2u562J6YeP5YWz57O75YiX5pa556iL57uEPC9wPg==
- 答案：Qg==
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
本课配套习题挑战模式3/5
单选题
难度系数：
3.要用21张白卡纸做长方体的包装盒，准备把这些白卡纸分成两部分，一部分x张做侧面，另一部分y张做底面，已知每张白卡纸可以做侧面2个，或做底面3个，如果1个侧面可以和2个底面做成一个包装盒，依题意列方程组为（ ）
A:  |
B:  |
C:  |
D:  |
一次做对，真牛！
+5奖励规则>
- 提示1：IOiuvueUqHjlvKDnmb3ljaHnurjlgZrkvqfpnaLvvIznlKh55byg55m95Y2h57q45YGa5bqV6Z2i77yM5YiZ5YGa5Ye65L6n6Z2i55qE5pWw6YeP5Li6MnjvvIzlupXpnaLnmoTmlbDph4/kuLozee+8mw==
- 提示2：IOagueaNruetiemHj+WFs+ezu++8muKAnOeZveWNoee6uOaAu+aVsOS4ujIx5byg4oCd5b6X5pa556iL5LiA77yb
- 提示3：IOagueaNruetiemHj+WFs+ezu++8muW6lemdouaVsOmHjz3kvqfpnaLmlbDph4/nmoQy5YCN77yM5YiX5Ye65pa556iL57uE5Y2z5Y+vLg==
- 答案：Qw==
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
本课配套习题挑战模式4/5
单选题
难度系数：
4.
《九章算术》是我国东汉年间编订的一部数学经典著作，在它的“方程”一章里一次方程组是由算筹布置而成的. 《九章算术》中的算筹图是竖排的，为看图方便，把它改为横排，如图（1）、（2），图中各行从左到右列出的算筹数分别表示未知数x，y的系数与对应的常数项，把图（1）所示的算筹图中方程组形式表述出来，就是
类似地，图②可表示的算筹图可表示为（ ）
| A:
|
| B:
|
| C:
|
| D:
|
一次做对，真牛！
+5奖励规则>
- 提示1：PHA+5qC55o2u5Zu+Me+8jOe7k+WQiOW3suefpeeahOaWueeoi+e7hOeQhuino+eul+etueihqOekuueahOWunumZheaVsOWtl+aJvuinhOW+izwvcD4=
- 提示2：PHA+5YmN5Lik6aG55piveOOAgXnnmoTns7vmlbDvvIzlkI7kuIDpobnmmK/mlrnnqIvlj7PovrnnmoTluLjmlbDpobnvvIzljYHkvY3mlbDnlKjmqKrnur/ooajnpLrvvIzkuKrkvY3mlbDnlKjnq5bnur/ooajnpLrvvIzmu6HkupTnlKjmqKrnur/ooajnpLouPC9wPg==
- 提示3：PHA+5oyJ5q2k6KeE5b6L77yM5b6X5Ye656ys5LqM5Liq5pa556iL57uEPC9wPg==
- 答案：QQ==
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
本课配套习题挑战模式5/5
单选题
难度系数：
5.从2007年4月18日零点起，铁路将实施第六次大提速，届时“子弹头”动力组列车的速度将大大提高. 若有一普通列车长为140米，“子弹头”动力组列车 长为110米，两列车若同向而行，两车交汇的时间为9秒，若两列车相向而行，两车交汇的时间为3秒，求“子弹头”动力组列车和普通列车的速度分别为多少？ 若设“子弹头”动力组列车的速度为x米/秒，普通列车速度为y米/秒，则可列出方程组为（ ）
A:  |
B:  |
C:  |
D:  |
一次做对，真牛！
+5奖励规则>
- 提示1：IOWKqOWKm+e7hDnnp5LnmoTot6/nqIst5pmu6YCa5YiX6L2mOeenkueahOi3r+eoiz3kuKTovabovabplb/kuYvlkow=
- 提示2：IOaZrumAmuWIl+i9pjPnp5LnmoTot6/nqIsr5Yqo5Yqb57uEM+enkueahOi3r+eoiz3kuKTovabovabplb/kuYvlkow=
- 提示3：IOagueaNruetiemHj+WFs+ezu+WIl+aWueeoi+e7hA==
- 答案：QQ==
PGRpdj7op6PvvJrmoLnmja7liqjlipvnu4Q556eS55qE6Lev56iLLeaZrumAmuWIl+i9pjnnp5LnmoTot6/nqIs95Lik6L2m6L2m6ZW/5LmL5ZKM77yM5b6X5pa556iLM3grM3k9MTQwKzExMO+8mzxicj7moLnmja7mma7pgJrliJfovaYz56eS55qE6Lev56iLK+WKqOWKm+e7hDPnp5LnmoTot6/nqIs95Lik6L2m6L2m6ZW/5LmL5ZKM77yM5b6X5pa556iLOXgtOXk9MTQwKzExMC4gPC9kaXY+PGRpdj7lj6/liJfmlrnnqIvnu4TkuLrvvJo8aW1nIHdpZHRoPTEzNSBoZWlnaHQ9NDIgc3JjPSJodHRwczovL3AyLnFpbmdndW8uY29tL0cxL00wMC8yMy80NS9yQkFDRTFNTVVzeXdGbXg4QUFBRHYzZmptMmM1MzEucG5nIj48L2Rpdj4=
