SOLUTION: I'm so sorry. I just sent you a question and gave you the wrong email address. I am a tutor, trying to get help for a student who needs to solve this problem. Can you please hel

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Question 714630: I'm so sorry. I just sent you a question and gave you the wrong email address. I am a tutor, trying to get help for a student who needs to solve this problem. Can you please help?
Thank you so much!
Renee Bridgman (this time I entered the correct email server!)
William's wallet contains three $1 bills, four
$5 bills, and two $10 bills. If William chooses
two bills at random, what is the probability of
selecting a $1 bill and then a $10 bill?
A. 2/27
B. 1/12
C. 7/12
D. 5/6

Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

You have:
3 $1 bills,
4 $5 bills, and
2 $10 bills
if you select a bill at random, without replacing the bill, you choose a second bill at random
first find p of $1 bill, then $10
there are 9 bills in total, and 3 of which are $1, the probability of choosing a $1 first is p=3%2F9 or p=1%2F3
so, 1%2F3 of the times you try you will select a $1 first
if you select a $1 first and don't replace it, there are 8 bills left to select second, 2 of which are $10
so 2%2F8=1%2F4 of those times when you selected a $1 first, you will select a $10 second
finally, you will select a $10 bill second 1%2F4 of the 1%2F3
of the times when you select a ten first. So the desired probability is
1%2F3%2A1%2F4+=+1%2F12.......so, your answer is B