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Diffstat (limited to 'houdre')
| -rw-r--r-- | houdre/hw1.tex | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/houdre/hw1.tex b/houdre/hw1.tex index 4baddda..c06f5fa 100644 --- a/houdre/hw1.tex +++ b/houdre/hw1.tex @@ -136,6 +136,8 @@ These are both calculated using inclusion-exclusion, the first being three independent events with probabilities $(p^2,p^2,p)$ and the second being several dependent probabilities. +% Insufficient explanation (6/10) + \q14 $$\Pr(A\cup B) = \Pr(A\setminus B)+\Pr(B\setminus A)+\Pr(A\cap B)$$ @@ -247,4 +249,7 @@ $$= 3\Pr(\hbox{matched red}) = 3{6\over(3+n)(2+n)} This means that the probability of matched black socks is the same as the probability of matched red socks: ${6\over(3+3)(2+3)} = {1\over5}$. +% This is mostly correct, but n is actually the total number of socks, +% so n=6. 2/10 + \bye |