Grover will earn $0.50 x 20 = $<<0.50*20=10>>10 for each box.

So, he will earn $10 x 3 = $<<10*3=30>>30 after selling all the face masks.

Therefore, his total profit will be $30 - $15 = $<<30-15=15>>15.

# Answer

15
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Grover bought 3 boxes of face masks. He plans to sell them for $0.50 each. If each box has 20 face masks, and he bought the 3 boxes for $15, how much will be his total profit?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
15
Grover bought 3 boxes of face masks. He plans to sell them for $0.50 each. If each box has 20 face masks, and he bought the 3 boxes for $15, how much will be his total profit?
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