Задание №81562 ЕГЭ Английскому языку

Преобразуйте, если это необходимо, слово «PAY» так, чтобы оно грамматически соответствовало содержанию текста.

As the old woman was leaving, he called out, "Goodbye mother!" As he stepped up to the checkout counter, he saw that his total was $127.50. "How can that be?" eh asked, "I only bought a few things!" "Your mother said that you ______________ for her," said the clerk.