During a sale, the price of a sweater was changed from $20 to $16. what was the percent of the decrease in the price of the sweater?

( show work: ) )

One-third of the people from country a claim that they are from country b, and the rest admit they are from country a. one-fourth of the people from country claim that they are from country a, and the rest admit they are from country b. in a combined census of the two countries, one-half of the total claimed to be from a. what is the ratio of the populations of country a to that of country b.

Me! 50 points! why does when we come home, our door is unlocked and there is grease on the door knob, me solve this , and i don't know what category this goes under

Why is causation so much more difficult to prove than correlation?