Since the problem says "(strictly) between $20$ and $60$", the numbers $20$ and $60$ are not included.

When a statement like "between $a$ and $b$" can be ambiguous, we usually say "strictly between $a$ and $b$" or "between $a$ and $b$ (inclusive)" to distinguish the case where we do not include $a$ and $b$, and when we include $a$ and $b$.