As many as you can fit.
http://wiki.answers.com/Q/How_many_cups_of_sugar_a...

1 lb. of sugar = 2 1/4 cups so 5 lb. = 11 1/4 cups. ChaCha again soon!
http://www.chacha.com/question/howmanycupsarei...

Approximately 2 cups of sugar equals 1 pound in weight, so a 5 pound sugar bag contains 10 cups of sugar. It is true because sugar has about the same densitiy as water, and 1 cup
http://www.webanswers.com/fooddrink/cooking/howm...

1. Multiply the number of pounds of sugar the recipe calls for by 3.75 to find out how many cups of sifted powdered sugar you need. 2. Set the appropriate measuring cup in a large
http://www.ehow.com/how_8182644_substitutecupspo...
