Answer:
80% probability that it will take Victoria greater than 8 minutes (total) for a puzzle that she has already been working on for 7 minutes
Explanation:
An uniform probability is a case of probability in which each outcome is equally as likely.
For this situation, we have a lower limit of the distribution that we call a and an upper limit that we call b.
The probability that we find a value X greater than x is given by the following formula.
![P(X > x) = 1 - (x - a)/(b-a)](https://img.qammunity.org/2021/formulas/mathematics/college/n8xt032dkhrmnenl5umzoz8q8pz5qxzyzl.png)
Uniformly distributed random time between 4 minutes and 12 minutes.
This means that
![a = 4, b = 12](https://img.qammunity.org/2021/formulas/mathematics/college/ph1i7cvfaas9o0qmv482e9qipizot07jp3.png)
What is the probability that it will take Victoria greater than 8 minutes (total) for a puzzle that she has already been working on for 7 minutes?
Already working for 7 minutes, so a is updated to 7.
![P(X > 8) = 1 - (8 - 7)/(12 - 7) = 0.8](https://img.qammunity.org/2021/formulas/mathematics/college/5p91sxvsfofd7aq12t4udth5qb08u6wj75.png)
80% probability that it will take Victoria greater than 8 minutes (total) for a puzzle that she has already been working on for 7 minutes