The short answer is that it depends on the powder.
For example, 1 lb of all purpose flour is approximately 4.5 U.S. cups while 1 lb of whole wheat flour is approximately 3.5 U.S. cups. I use "approximately" because how compacted the flour is will affect how much fits in a cup. Sifted flour has more volume than unsifted, for example.
But 1 lb of flour is still 1 lb of flour whether it is sifted or not. Because volume measures are so variable especially for powders, measuring by weight is what professional and expert bakers use.
A one-pound package of dry beans equals about 2 cups dry, or 5-6 cups cooked.
Approximately 3.6 cups to a pound of dry bowtie pasta.
A half pound of dry macaroni is typically equivalent to about 2 cups in volume.
A one pound bag of beans has about 2 cups of uncooked beans. When cooked it is 5-6 cups.
Somewhere between 100 and 125 cups in 60 lbs of sauce
About 2/3 a cup of dry pinto beans will result in one pound of cooked pinto beans. One pound of dry pinto beans = 2 cups of dry beans = 6 cups of cooked pinto beans 2 cups of cooked beans = about 16 ounces = one pound of cooked beans
Three and 1/2 cups
One pound of dry lentils typically yields about 2.5 to 3 cups of cooked lentils. When cooked, lentils roughly triple in volume, so from one pound (which is approximately 2 cups dry), you can expect to get around 6 cups of cooked lentils. The exact amount can vary slightly depending on the type of lentils and the cooking method used.
Three cups of cornstarch in one pound.
how many cups are in a one pound box of confectioners sugar?
how many cups is a fourth pound of butter?
based on a website that showed up on a google search, 4 cups = 1lbs