In order to get the suggested answer we must make several assumptions.I would really appreciate some help with this problem, number 45. The answer is at least seven. How? Thanks!
Typo: you mean \(\displaystyle 3^{-n}\le 10^{-3}\) or \(\displaystyle 3^n\ge 10^3\).In order to get the suggested answer we must make several assumptions.
Assume that the problem is about one guess out of the total possible.
Now for any \(\displaystyle n\in\mathbb{Z}^+\) then there are \(\displaystyle 3^n\) possible pass words.
So solve \(\displaystyle 3^{-n}\ge 10^{-3}\).