Tobias’s closet has 1 red hat and 1 black hat; 1 white shirt, 1 black shirt, and 1 black-and-white-striped shirt; and 1 pair of
black pants and 1 pair of blue pants. He is picking an outfit by reaching into his closet and randomly choosing a hat, a shirt, and a pair of pants. How many possible outfit combinations are there?
The perimeter of the rectangle is equal to the doubled sum of the sides, and the area is equal to the product of the sides. So we have the following equation