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杨琦同学记录了一次数学试验课的过程,下面我们就去看一看吧.人教版数学教科书七年级下册第144页安排了探究活动.老师提前一周就布置同桌两人要带来一瓶豆子,好做试验.数学课上也做试验,对我们来说很新鲜,所以大家都很期待.终于等到了数学试验课,我们两人一小组,按照课本上的操作步骤开始了试验.(1)从瓶子中取出一些豆子,我们小组数出这些豆子的粒数m,m=12;(2)给这些豆子做上记号;(3)把这些做上记号的豆子放回瓶子中,充分摇匀;(4)从瓶子中再取出一些豆子,数出这些豆子的粒数p,p=16,其中带有记号的豆子的粒数为n,n=4;(5)估计原来瓶子中豆子的总粒数q,q≈(16)/4×12=48;(6)数出瓶子中豆子的总粒数为51.老师让几个小组汇报了试验结果,其中我们小组估计出来的总粒数最接近实际总粒数,而有些小组的估计值严重偏离实际.这是什么原因呢?原来,有些小组带的是小瓶,只装了不到30粒豆子,总粒数太少;有些小组虽然带来的
Yang Qi students recorded a course of math test, we will have a look at it.Physical Education Edition Mathematics Textbook Volume VII of the next page 144th arranged for inquiry activities.A week earlier teacher to bring the same table to bring A bottle of beans, good to do the test .Mathematics class also test, for us is very fresh, so we are looking forward to finally wait until the math test class, we a small group of two, according to textbooks on the steps to start the experiment . (1) Remove some of the beans from the bottle, and our group counts the number of these beans in m, m = 12; (2) Mark the beans; (3) Put the marked beans back into the bottle , Shake well; (4) remove some beans from the bottle again, count out the number of these beans p, p = 16, where the number of beans marked with n, n = 4; The total number of beans in the bottle q, q ≈ (16) / 4 × 12 = 48; (6) count out the total number of beans in the bottle is 51. The teacher reported to several groups test results, of which our group estimates Out of the total number of particles closest to the actual total number of particles, and some groups seriously deviate from the actual estimates. What is the reason? It turned out that some groups with Vial, only packed with less than 30 beans, the total number of particles too small; although some groups brought