Answer:
=(k−1)*P(X>k−1) or (k−1)365k(365k−1)(k−1)!
Step-by-step explanation:
First of all, we need to find PMF
Let X = k represent the case in which there is no birthday match within (k-1) people
However, there is a birthday match when kth person arrives
Hence, there is 365^k possibilities in birthday arrangements
Supposing (k-1) dates are placed on specific days in a year
Pick one of k-1 of them & make it the date of the kth person that arrives, then:
The CDF is P(X≤k)=(1−(365k)k)/!365k, so the can obtain the PMF by
P(X=k) =P (X≤k) − P(X≤k−1)=(1−(365k)k!/365^k)−(1−(365k−1)(k−1)!/365^(k−1))=
(k−1)/365^k * (365k−1) * (k−1)!
=(k−1)*(1−P(X≤k−1))
=(k−1)*P(X>k−1)
Answer:
Step-by-step explanation:
y = 5x + 20
Start at (0, 20).
Then plot a point at (1, 25).
The line should be going through points (2, 30), (3, 35), (4, 40), (5, 45), etc.
For every time the x number goes up, the y number goes up 5 times for the 5%.
Answer:
q = 108-n
Step-by-step explanation:
Given: 108 coins containing only quarters and nickels
q = 108-n
since total number of coins is 108, and n= number of nickels
If you want to know how many of each kind of coin, read on:
First solve the number of quarters and nickels.
If all 108 coins are quarters, the value is 108*0.25 = $27
Since this value exceed the actual by 27-21 = $6,
we replace a number of quarters by nickels.
Each replacement will reduce the value by 25 - 5 = 20 cents = 0.2 dollars.
So it will take 6/0.2 = 30 replacements.
Therefore there are 108-35 = 78 quarters and 30 nickels.
