The amount of the discount is 20/100 * $90 original price = $<<20/100*90=18>>18

Charlotte needs to bring the $90 - $18 discount = $<<90-18=72>>72

# Answer

72
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Charlotte needs to know how much money to have with her when she goes to the shoe store. How much money should Charlotte bring to buy a pair of boots, if the original price is $90 and there is a discount of 20%?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
72
Charlotte needs to know how much money to have with her when she goes to the shoe store. How much money should Charlotte bring to buy a pair of boots, if the original price is $90 and there is a discount of 20%?
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