Mario's $18 cut on Monday would have been 50% more expensive on Sunday or $18*50% = $<<18*50*.01=9>>9 more expensive

That means he would have paid $9 more on Sunday than what he paid ($18) on Monday or $9+$18 = $<<9+18=27>>27

# Answer

27
<|im_start|>system
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<|im_start|>user
At Mario's barbershop haircuts are 50% more expensive during the weekends. If Mario paid $18 for his last haircut on Monday, how much he would have paid the day before?
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user
27
At Mario's barbershop haircuts are 50% more expensive during the weekends. If Mario paid $18 for his last haircut on Monday, how much he would have paid the day before?
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