Look at each row separately in the questions, you need to count up in 1s.
Example:
Row 4: 453, ______, ______ , 456 , ______ , 458
Row 6: 721, ______ , 723 , _____, _____, 726
Row 4: 453, __454_, _455__ , 456 , _457__ , 458
Row 6: 721, _722__ , 723 , _724_, _725_, 726
