She saw right away that the additional tiles that you had to add around the edges was always going to grow by two, so she was very confident about how she made those numbers there.
Тя веднага забелязва, че допълнителните елементи, които трябва да прибави около ръбовете винаги нарастват два пъти. И тя е много уверена, че тези числа са верни.