<div style="text-align: center;"><strong><font color="#ff0000">北师大版四年级下册数学第三单元练习（2017.3.31）</font></strong></div><br><div style="text-align: center;">班级 座号 姓名 成绩 </div><br><span><strong>一、填空题。</strong></span><br><br><span>1.</span><span>0.3×4</span><span>表示</span><span>(</span><span> </span><span>)</span><span>个</span><span>(</span><span> </span><span>)</span><span>相加。</span><br><br><span>2.0.29×0.07</span><span>的积有</span><span>(</span><span> </span><span>)</span><span>位小数</span><span>,</span><span>6.5×8.4</span><span>的积有</span><span>(</span><span> </span><span>)</span><span>位小数。</span><br><br><span>3.0.65</span><span>扩大到原来的</span><span>100</span><span>倍是</span><span>(</span><span> </span><span>),</span><span>0.052</span><span>扩大到原来的</span><span>(</span><span> </span><span>)</span><span>倍是</span><span>52</span><span>。</span><br><br><span>4.</span><span>根据</span><span>32×15=480</span><span>填空。</span><br><br><span>3.2×15=</span><span>(</span><span> </span><span>)</span><span> 3.2×1.5=</span><span>(</span><span> </span><span>)</span><span> </span><span>32×0.15=</span><span>(</span><span> </span><span>)</span><span></span><span>32×1.5=</span><span>(</span><span> </span><span>)</span><br><br><span>5.</span><span>把</span><span>28.5</span><span>的小数点向</span><span>(</span><span> </span><span>)</span><span>移动两位</span><span>,</span><span>这个数就缩小到原来的。</span><br><br><span>6.3.5×</span><span>(</span><span>10+0.1</span><span>)</span><span>=3.5×</span><span>(</span><span> </span><span>)</span><span>+3.5×</span><span>(</span><span> </span><span>)</span><br><br><span>7.6.3×16.89的积是（ ）位小数，结果是（ ）。</span><br><br><span>8.算式3.6×a，当a（ ）1时，乘积大于3.6；当a（ ）1时，乘积小于3.6；当a（ ）1时，乘积等于3.6。</span><br><br><span>9</span><span>.</span><span>在</span><span>Ο里填上“</span><span>></span><span>”“</span><span><</span><span>”或“</span><span>=</span><span>”。</span><br><span><br></span><div><span>2.75×1.02</span>Ο2.75 0.98×0.98Ο0.98</div><div><br></div><div>1.8Ο1.8×0.8 0.26×1Ο0.26</div><div><br><span>10.两个因数的积是0.68，若将其中一个因数扩大10倍，另一个因数不变，那么积是 （ ）；若将其中一个因数扩大100倍，另一个因数缩小到它的1/100，那么积是（ ）。</span><br><br><span>11.小数混合运算的运算顺序和整数混合运算的顺序（ ），没有括号的，要先算（ ），再算（ ）；有括号的，要先算（ ）。</span><br><br><span>12.5.4×0.6+5.4×0.4= ×（ + ），这个算式运用了乘法（ ）。</span><span> </span><br><br><strong><span>二、判断题。</span><span>(</span><span>对的画“</span><span>√”</span><span>,</span><span>错的画“</span><span>✕</span><span>”</span><span>)</span></strong><br><br><span>1.</span><span>一个数的小数点向左移动一位</span><span>,</span><span>这个数就扩大到原来的</span><span>10</span><span>倍。</span><span></span><span>(</span><span> </span><span>)</span><br><br><span>2.8</span><span>乘一个小数</span><span>,</span><span>积一定比</span><span>8</span><span>小。</span><span></span><span>(</span><span> </span><span>)</span><br><br><span>3.0.75</span><span>扩大到原来的</span><span>10</span><span>倍等于</span><span>750</span><span>缩小到原来的。</span><span></span><span>(</span><span> </span><span>)</span><br><br><span>4.</span><span>两个小数相乘</span><span>,</span><span>所得的积一定比其中一个数大。</span><span></span><span>(</span><span> </span><span>)</span><br><br><span>5.</span><span>整数的运算定律在小数中仍然适用。</span><span></span><span>(</span><span> </span><span>)</span><br><br><span><strong>三、计算。</strong></span><br><br><span>1.</span><span>直接写得数。</span><br><br><span>70×0.001=</span><span> </span><span> 2.515×10=</span><span> </span><span>1.1×0.4=</span></div><div><span><br></span></div><div><span>0.326×100=</span><span> </span><span>0.1×0.01=</span><span> </span><span>0.87-0.6=</span><br><br><span>2.</span><span>用竖式计算</span><br><br><span>2.1×2.15=</span><span> </span><span></span><span>4.8×0.25=</span></div><div><span><br></span></div><div><span><br></span></div><div><span>6.05×0.54=</span><span> </span>*4.2×1.01=</div><div><br><br><span>3.</span><span>用简便方法计算。</span><br><br><span>0.125×9.3×80</span><span> </span><span>0.8×0.6+0.32</span></div><div><span><br></span></div><div><span><br></span></div><div><span>4.8×3.6-3.8×3.6</span><span> </span><span>9.9×13.6</span><br><br><br><span><strong>四、解决问题。</strong></span><br><br><span>1.</span><span>学校宣传栏上的一块长</span><span>2.4</span><span>米、宽</span><span>1.2</span><span>米的玻璃碎了</span><span>,</span><span>需要更换一块新玻璃。</span><br><br><span>(</span><span>1</span><span>)</span><span>更换新玻璃的面积是多少</span><span>?</span><span> </span><span>(</span><span>2</span><span>)</span><span>如果每平方米玻璃</span><span>10</span><span>元</span><span>,</span><span>买这样一块玻璃需要多少元</span><span>?</span><br><br><span>2.</span><span>苹果每千克</span><span>3.25</span><span>元</span><span>,</span><span>爸爸买了</span><span>14</span><span>千克苹果</span><span>,</span><span>付了</span><span>50</span><span>元</span><span>,</span><span>应找回多少元</span><span>?</span><br><br><span>3.</span><span>在唱歌比赛中</span><span>,</span><span>有</span><span>3</span><span>位评委给小宇打了</span><span>9.08</span><span>分</span><span>,</span><span>有</span><span>4</span><span>位评委给她打了</span><span>9.27</span><span>分。小宇的总分是多少分</span><span>?</span><br><br><span>4.</span><span>回收</span><span>1</span><span>吨废纸可以少砍伐</span><span>16</span><span>棵树</span><span>,</span><span>回收</span><span>4500</span><span>千克废纸可以少砍伐多少棵树</span><span>?</span><br><br><span>5.一箱香蕉15.5千克，王叔叔用三轮车一次可以运16箱，要全部运完得运4次。王叔叔得运多少千克的香蕉？</span><br><br><span>6.乌龟爬行的速度大约是每秒0.05米，兔子奔跑的速度大约是乌龟的280倍。兔子的速度比乌龟快多少？</span><br><br><span>7.学校买来122把椅子和60张桌子，每把椅子26.5元，桌子的单价是椅子的1.8倍。买桌子和椅子一共用了多少元钱？</span><br><br><span>8.某停车场每辆汽车停车一次至少收费5元，如果超过2时，每多停1时（不足1时按1时算）要多交0.6元。一辆汽车在停车场停了4时16分，这辆汽车的司机应停车费多少元？</span><br><br><span>9.小强和小红一起跳绳，小强每分钟跳72下，小红每分钟跳136下。1.5分钟内他们一共跳了多少下？</span><br><br></div>
四年级下