SOLUTION: Beth has a quarter, a dime and a nickel in her pocket. She pulls out two coins at random. What is the expected value of the coins?

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Question 865854: Beth has a quarter, a dime and a nickel in her pocket. She pulls out two coins at random. What is the expected value of the coins?
Found 2 solutions by Fombitz, richwmiller:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
P%28Q%29=1%2F3
P%28D%29=1%2F3
P%28N%29=1%2F3
Look at the possible choices.
P%28QD%29=+%281%2F3%29%281%2F3%29=+1%2F9 , V%28QD%29=25%2B10=35
P%28QN%29=%281%2F3%29%281%2F3%29=1%2F9, V%28QN%29=25%2B5=30
P%28DQ%29=%281%2F3%29%281%2F3%29=1%2F9,+V%28DQ%29=10%2B25=35
P%28DN%29=%281%2F3%29%281%2F3%29=1%2F9, V%28DN%29=10%2B5=15
P%28ND%29=%281%2F3%29%281%2F3%29=1%2F9, V%28NQ%29=5%2B25=30
P%28NQ%29=%281%2F3%29%281%2F3%29=1%2F9, V%28ND%29=5%2B10=15

E=+160%2F9


Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
There are only six possible combinations
25+10=35
25+5=30
10+25=35
10+5=15
5+25=30
5+10=15
Each is equally likely.
which brings us to three possible sums
15,30,35 which each occur twice
which gives each sum 2 out of 6 chance or 1 out of 3
add them up and we get 80
80/3=26.67
so 26.67