## Thinking Mathematically (6th Edition)

$\emptyset \subseteq \{101, 102, 103,... , 200\}$ $\emptyset \subset \{101, 102, 103,... , 200\}$
$\emptyset$____$\{101, 102, 103,... , 200\}$ By definition, an empty set is a subset of every set, and is a proper subset of every set except another empty subset, therefore: $\emptyset \subseteq \{101, 102, 103,... , 200\}$ $\emptyset \subset \{101, 102, 103,... , 200\}$