Hello, can you help me solve my maths problem? NAME_1's mother sends him to the shop to buy €15 of olive oil. She gives him a €20 note to pay. NAME_1 buys the oil in the shop and the cashier gives him change by giving him a €1 coin and a €2 coin. When he gets home, NAME_1 gives the olive oil and the change to his mother. She does not agree with the amount of money NAME_1 gives her and is angry. Explain why. Provide two versions of response separated with exactly 6 asterisk symbols: ******.
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