Question

图表显示了一个数学班 $30$ 名学生在最近两次测验中的成绩分布。例如，正好有一名学生在第一次测验中得 D，在第二次测验中得 C（圈出的格子）。有百分之多少的学生两次测验得到了相同成绩？

The table shown displays the grade distribution of the $30$ students in a mathematics class on the last two tests. For example, exactly one student received a 'D' on Test 1 and a 'C' on Test 2 (the circled entry). What percent of the students received the same grade on both tests?

$12\%$

$25\%$

$33\dfrac13\%$

$40\%$

$50\%$

答案：D

知识点：数据与图表解读百分数

难度评级：860

解答：

学生两次测验成绩相同，正对应主对角线上的格子。这些数是 $2 + 4 + 5 + 1 + 0 = 12$ 。

所以比例是 $\dfrac{12}{30} = \dfrac{4}{10} = 40\%$ 。

所以正确答案是 D。

A student received the same grade on both tests exactly when counted on the main diagonal. Those entries are $2 + 4 + 5 + 1 + 0 = 12.$

So the fraction is $\dfrac{12}{30} = \dfrac{4}{10} = 40\%.$

Thus, the correct answer is D .

1986 AMC 8 第 12 题

答案：D

难度评级：860

解答：

其他年份的第 12 题