Answer:
2 possible answers
Explanation:
Assumption: 178 wore black (that means some may wear gold + black aka as long as they wore abit of black, it's counted):
since there are 257 students and 34 wore both gold and black, and 178 wore black, the number of students who wore only black = 178 - 34 = 144
no of students who wore only gold = 257 - 144 - 34 = 79
Assumption: 178 students wore ONLY black:
no of students who wore only gold: 257 - 178 - 34 = 45
Topic: Set theory
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