A dad holds five coins in his hand. He tells his son that if he can guess

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Question:

A dad holds five coins in his hand. He tells his son that if he can guess the amount of money he is holding within 5% percentage error he can have the money. The son guesses that he is holding 81 cents. The dad opens his hand and displays 90 cents. Did the son guess close enough to receive the money from his father?