2,8 2+8=10
4,6 4+6=10
Can’t be more than 10$’s. The multiples of 2 are 2,4,6,8,10. So you’re answering which 2 numbers add up to 10$. If it’s anything higher than that it’s not a possible price and if it’s lower than that then she would have payed less which also isn’t possible.