as far as I can tell, is referring and assuming the ruler doesn't have any fractional values, namely it only has markings with integers.
so in short is asking, what are the two integers that the fractional 5¼ is between?
[tex]\bf \boxed{5}\text{\textemdash\textemdash\textemdash}5\frac{1}{4}\text{\textemdash\textemdash\textemdash\textemdash\textemdash\textemdash\textemdash\textemdash\textemdash}\boxed{6}[/tex]