Brendan wants to buy a new pair of skates. He can buy hockey skates, in-line skates, roller skates, figure skates, or speed skates. A pair of skates can come in white, silver, black, or gold, and can be decorated with blue streaks, yellow stars, green clovers, orange pumpkins, or red lightning bolts. How many different combinations can Brendan choose from?

Brendan can choose from 5 types of skates and 4 colors, giving him 5 x 4 = 20 options so far. Each of these options can also be decorated in 5 different ways, giving him a total of 20 x 5 = 100 different combinations. Therefore, Brendan has 100 options to choose from.