EPTI've never taken a probability course and I don't know how to approach these questions systematically. I've included my own reasoning. I assume they're elementary for anyone that's taken an intro to probability course. I think I've helped out a fair share of people in math on these blogs so I hope someone can karma me.
In a box of m&ms,
24% are blue
20% orange
16% green
14% yellow
13% red
13% brown
What is the probability that at least one is blue?
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My reasoning would be let B be the space of 'pick blue', and then Pr('at least one blue') = (1-B^c)^3, where B^c is the complement of B. Could anyone formalize the "long" way of doing it?
What is the probability that the third M&M is red?
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it seems obvious that it would just be 13% ... am I missing something?
Workers are assigned to different tasks each month in a company.
55% of employees have less than or equal to 2 years of experience
32% have between three and five years
13% have more than five
Assume that teams of 3 employees are randomly formed. Dave is in such a team.
a) What is the prob. that one of Dave's teammates has
1. two or fewer years of experience?
2. moe than five years of experience?
b) What is the prob. considering both of Dave's two teammates,
1. both have more than two years
2. exactly one has more than five years of experience
3. at least one has more than five years of experience?
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For this question I just see myself drawing a bunch of branching diagrams, but I would like to see a more formal approach to it.
I know set notation and basic probability notation, but I don't know enough or have enough time to logic through it right now, and I'd like to help a friend. Hope someone can help me out.
Cheers
