9514 1404 393
Answer:
7 : 9
Explanation:
If 45 of the 80 students were girls, then the remaining 35 will be assumed to be boys*. The ratio of boys to girls is ...
35 : 45 = 7 : 9
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* So far, math problems have only recognized gender identification as "boys" and "girls". This is not intended to insult anyone who has a different gender identification. Someday, issues of gender identification may be resolved in a different fashion. For now, we assume any student that is not a girl will be a boy.