Practice problem
Combination Notation
By Alex Federspiel
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Contributors
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Today (July 28) is National Hamburger Day!
Image by RitaE via [Pixabay](IMAGE ADDRESS) (CC0)
A hamburger restaurant lets you choose up to four toppings for free. The toppings include: iceberg lettuce, romaine lettuce, spinach, mayo, jalapeños, banana peppers, red onion, grilled onions, field greens, arugula, cucumbers, dill pickles, bread and butter pickles, and tomatoes.
How many different burgers can you make with four toppings?