<span>Probability = 0.063
Fourth try = 0.0973
Let X be the number of failed attempts at passing the test before the student passes. This
is a negative binomial or geometric variable with x â {0, 1, 2, 3, . . .}, p = P(success) = 0.7
and the number of successes to to observe r = 1. Thus the pmf is nb(x; 1, p) = (1 â’ p)
xp.
The probability P that the student passes on the third try means that there were x = 2
failed attempts or P = nb(2, ; 1, .7) = (.3)2
(.7) = 0.063 . The probability that the student
passes before the third try is that there were two or fewer failed attmpts, so P = P(X ≤
2) = nb(0, ; 1, .7) + nb(1, ; 1, .7) + nb(2, ; 1, .7) = (.3)0
(.7) + (.3)1
(.7) + (.3)2
(.7) = 0.973 .</span>
Answer:
10
Step-by-step explanation:
This means that 12/(2x+1)=8/(x+4). Cross multiply to get 16x + 8 = 12x + 48. Subtract 12x + 8 from both sides to get 4x = 40, so x = 10.
Answer:
The balance of Dianne's register should be $359.41
Step-by-step explanation:
We can begin at the ending balance on the bank statement at $578.30
Then a check is written for $219.25, so a debit
Next a deposit is made for $140.36, so a credit
Then a withdrawal is made for $140.00, so a debit
This means we can make the equation
Answer:
9/25x^2 -25
Step-by-step explanation:
