Answer:
2775 ways
Step-by-step explanation:
We have been given the case to choose exactly two tails when flipped 75 times means
Since, is equal to
Here n =75, r=2 substituting the values we will get
After simplification we will get
Cancel out the common term that is 73! we will get
after more simplification we will get
Finally, we will get
Answer:
It takes less time sending 5 letters the traditional way with a probability of 36.7%.
Step-by-step explanation:
First we must take into account that:
- The traditional method is distributed X ~ Poisson(L = 1)
- The new method is distributed X ~ Poisson(L = 5)
Where L is the intensity in which the events happen in a time unit and x is the number of events.
To solve the problem we must calculate the probability of events (to send 5 letters) in a unit of time for both methods, so:
- For the traditional method:
- For the new method:
According to this calculations we have a higher probability of sending 5 letters with the traditional method in a unit of time, that is 36.7%. Whereas sending 5 letters with the new method is less probable in a unit of time. In other words, we have more events per unit of time with the traditional method.