A survey on “What apps students use to learn English” was made in Class 4, Grade 9 in Xinhua Middle School. There are 100 students in this class. One fifth of them don’t learn English by app. Then according to the form below, among the students who learn English by app, __________ students use Scallops Words.
BaiCiZhan (百词斩) | Scallops Words (扇贝单词) | Youdao Dictionary (有道词典) | PowerWord (金山词霸) |
50% | ? | 10% | 15% |
A.40 B.20 C.12