问题求解，题目看起来简单，可是不明白具体意思。。。 highest

c8143

Question 27


Twenty students take an exam. The percentages of questions they answer correctly are ranked from lowest to highest as follows:

32	49	57	58	61
62	64	66	67	67
68	69	71	72	72
74	76	80	82	83

In a frequency distribution from 30% to 90% that is divided into six equal-sized intervals, the absolute frequency of the sixth interval is:

A) 2.

B) 4.

C) 1.

D) 3.


有个帖子给的答案是 D，我不明白，求解！

cheng302a

回复 1# c8143
The sixth interval is 80%-90%，so 80%，82%，83% is included，3 is correct。

sophiaus

30%-90% into 6 bins:    (90-30)/6 = 10.
                           Bin 1:    30%-40%
                                 2:  40%-50%
                                 3: 50%-60%           4: 60%-70%     5: 70%-80%
                                 6: 80%-90%
Question asking about the sixth interval's frequency, which is the frequency between 80%-90%. There are 3 of it (80%, 82%, 83%). Answer is D.

小王帅太阳

新人，题目看懂了，只是全英文也未免太难了吧

liushuai91

考得其实是英语

JasonZ666

一楼正解，二楼详解