Please help confused?
Antonio is a freelance computer programer. In his work, he often uses the power of 2n to find the number of ways bits (or units of information) can be arranged. The n often stands for the number of bits.
Antonio is working on programming a new video game called Millie's Quest. In the game, the main character, Millie, collects golden keys to help her in her quest. Antonio wants to write a formula to show that Millie can collect one less key than the highest number of bits that can be arranged in the system. What formula can he use?

Given : Antonio uses the power of 2n to find the number of ways bits can be arranged. The n often stands for the number of bits. Millie, collects golden keys to help her in her quest.

To write : A formula to show that Millie can collect one less key than the highest number of bits that can be arranged in the system.

Number of bits =n

Highest number of bits =2n

One less key than the highest number of bits = 2n-1

Therefore, the formula he use = 2n-1