. Olivia filled 4 baskets of apples. Her friend filled up one additional basket of

apples. If all of the baskets sold for a total of $160, how much money did
each basket of apples cost?

Olivia filled 4 baskets of apples and her friend filled one additional basket, so there were a total of 4 + 1 = <<4+1=5>>5 baskets.

If all of the baskets sold for $160, then each basket of apples cost $160 / 5 = $<<160/5=32>>32. Answer: \boxed{32}.