Question

下表给出安维尔和克利奥纳两所小学各年级学生所占百分比：

	$K$	$1$	$2$	$3$	$4$	$5$	$6$
安维尔	$16\%$	$15\%$	$15\%$	$14\%$	$13\%$	$16\%$	$11\%$
克利奥纳	$12\%$	$15\%$	$14\%$	$13\%$	$15\%$	$14\%$	$17\%$

安维尔有 $100$ 名学生，克利奥纳有 $200$ 名学生。两所学校合计，有百分之几的学生在 $6$ 年级？

The table below gives the percent of students in each grade at Annville and Cleona elementary schools:

	$K$	$1$	$2$	$3$	$4$	$5$	$6$
Annville	$16\%$	$15\%$	$15\%$	$14\%$	$13\%$	$16\%$	$11\%$
Cleona	$12\%$	$15\%$	$14\%$	$13\%$	$15\%$	$14\%$	$17\%$

Annville has $100$ students and Cleona has $200$ students. In the two schools combined, what percent of the students are in grade $6?$

$12\%$

$13\%$

$14\%$

$15\%$

$28\%$

分别求每所学校的 $6$ 年级学生人数

Find the number of grade- $6$ students at each school separately

用两校合计的 $6$ 年级人数除以总人数 $300$

Divide the combined grade- $6$ count by the $300$ total students

安维尔的六年级人数为 $11\%$ 乘以 $100 = 11$ 人；克利奥纳的六年级人数为 $17\%$ 乘以 $200 = 34$ 人。

合计为 $11 + 34 = 45$ 人，占总人数 $300$ 的 $\dfrac{45}{300} = 15\%$ 。

所以正确答案是 D。

Annville has $11\%$ of $100 = 11$ sixth graders, and Cleona has $17\%$ of $200 = 34$ sixth graders.

Combined, that is $11 + 34 = 45$ out of $300$ students, which is $\dfrac{45}{300} = 15\%.$

Thus, the correct answer is D .