I am trying to solve this conditional and joint probability quiz. I am not able to answer one question. Can anyone help? I am trying to understand how any of the answer can be correct, because none of my calculation is leading to these answers.
The question is:
Consider a set containing all Science students OR all male students. What is the Probability that a randomly selected person will belong to this set?
The answers provided are:
- 40/90
- 50/90
- 310/500
- 260/500
I am not sure which formula to use for finding out this answer. Any help is appreciated. P.S - I also asked in stats group but I am not getting any answers so posting in math group as well hoping some math wiz can help me :)
| Science | Others | Total | |
|---|---|---|---|
| Male | 80 | 180 | 260 |
| Female | 70 | 170 | 240 |
| Total | 150 | 350 | 500 |
The correct answer results to me
$$\frac{150+260-80}{500}=\frac{330}{500}$$
Thus none of the provided answers