The GCD of given numbers is 2.
Step 1 : Find prime factorization of each number.
$$\begin{aligned}54 =& 2\cdot3\cdot3\cdot3\\[8pt]72 =& 2\cdot2\cdot2\cdot3\cdot3\\[8pt]72 =& 2\cdot2\cdot2\cdot3\cdot3\\[8pt]104 =& 2\cdot2\cdot2\cdot13\\[8pt]130 =& 2\cdot5\cdot13\\[8pt]\end{aligned}$$(view steps on how to factor 54, 72, 72, 104 and 130. )
Step 2 : Put a box around factors that are common for all numbers:
$$\begin{aligned}54 =& \color{blue}{\boxed{2}}\cdot3\cdot3\cdot3\\[8pt]72 =& \color{blue}{\boxed{2}}\cdot2\cdot2\cdot3\cdot3\\[8pt]72 =& \color{blue}{\boxed{2}}\cdot2\cdot2\cdot3\cdot3\\[8pt]104 =& \color{blue}{\boxed{2}}\cdot2\cdot2\cdot13\\[8pt]130 =& \color{blue}{\boxed{2}}\cdot5\cdot13\\[8pt]\end{aligned}$$Step 3 : Multiply the boxed numbers together:
$$ GCD = 2 $$