Probability: What Is Expected Value?

You are moving into your first apartment and purchase the toaster with the best reviews from a reputable brand for your kitchen. While checking out, the clerk asks you whether you'd like to buy a 1-year warranty for the toaster. The warranty is priced at 20% of the cost of the toaster. The amount of money in your savings account is 100 times the cost of the toaster. Should you buy the warranty?