Could you help me with the following problem? Thank you in advance.
I don't know the meaning of the underlined part. Three should be followed by a plural, but there's not any plural noun.
Twenty-five-year-old Alison works as a petrol pump assistant. She is a single mother looking after her toddler and is finding it a challenge to support herself and her child on her low salary.
When she found a lottery scratch-and-win card that has three matching “$75, 000” square revealed, she could have claimed the prize money.
The thought did occur in her mind for a moment, like many temptations that flit in and out of our minds. But Alison lived by some principles, one of them being “honesty is the best policy.”
The subject is a type of lottery ticket that you have to scratch off certain areas on the ticket. On this particular game, if you reveal three symbols that are the same, you win that prize. In this case, three symbols that said "$75,000" were revealed.