Joel gives 1/3 of his baseball cards to his sister. what is a fraction equivalent to 1/3

Write a recursive sequence that represents the sequence defined by the following explicit formula:

Awrestling tournament begins with 128 competitors. in the first round, each competitor has 1 match against another wrestler. the winner of each match moves on to the next round until there is a winner. write a sequence in which the terms represent the number of players still in the tournament at the end of each round. describe the sequence? how many rounds are in the tournament?

What is the value of x in the following equation. -x ^3/2 = -27