8.47 Overlapping distributions and English-language tests for international students: International students who wish to study at English-speaking universities in Canada or the United States are required to take a test, such as the Test of English as a Foreign Language (TOEFL) or the International English Language Testing System (IELTS), if English is not their first language. In a report of mean TOEFL scores by country, people whose first language was Serbian scored a mean of 86 (2015). People whose first language was Portuguese scored a mean of 82. Tijana, from Serbia, and Tomas, from Portugal, both just took the TOEFL.

a. Can we tell which student will do better on the TOEFL? Explain your answer.

b. Draw a picture that represents what the two distributions, that for people whose first language is Serbian and that for people whose first language is Portuguese, might look like with respect to one another. (Note that scores on the TOEFL range from 0 to 120.)