Answer: 45.4% of students like both building snowmen and skiing 
18.1% of students who do not like building snowmen also do not like skiing 
Step-by-step explanation:
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                  likes snowmen        doesn't like snowmen           total 
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  likes skiing    50                                30                                       80
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doesn't like skiing   10                             20                                30
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total                       60                                       50                         110