One-Half cup of black provides 15% of the potassium you need daily. You must get the remaining 2890 milligrams from other sources. How many milligrams of potassium should you consume daily?

Since the remaining 2890 milligrams is 100-15=85 percent of the potassium you need, we need to find how much 100% is. We can do this by dividing it by 8.5 to get 10 percent, and multiplying that by 10 to get 100%. This is 340*10=3400