## Elementary Algebra

$16$
Factor each number completely to have: $32 = 2 \cdot 2 \cdot 2 \cdot 2 \cdot 2 \\80 = 2 \cdot 2 \cdot 2 \cdot 2 \cdot 5 \\96= 2 \cdot 2 \cdot 2 \cdot 2 \cdot 2 \cdot 3$ Since four 2s are common to both, the greatest common factor of the given numbers is: $2 \cdot 2\cdot 2\cdot 2 = 16$