There are 30 bills in the envelope total. After the first bill is removed and not returned, there are 29 bills remaining.
The probability of the first bill being a $10 bill is 5/30 or 1/6.
After one $10 bill is removed, there are still four $10 bills remaining, 10 $20 bills, and 15 $50 bills. This means there are 29-1 = 28 bills remaining.
The probability of the second bill being a $50 bill (assuming the first bill was a $10 bill and was not returned) is 15/28.
To find the probability of both events occurring, we multiply the probabilities:
P($10 bill then $50 bill) = (1/6) x (15/28)
P($10 bill then $50 bill) = 5/56 = 0.0893 (rounded to four decimal places)
Therefore, the probability of getting a $10 bill and then a $50 bill is 5/56 or 0.0893.
A money envelope contains five $10 bills, ten $20 bills, and fifteen $50 bills. Sandra randomly selects two bills without returning the first bill. What is the probability of getting a $10 bill then a $50 bill? Write your answer in the simplest form of fraction
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