Answer:
C.
Step-by-step explanation:
sorry if its not correct but i hope it helps
54750 days / 365 (number of days in a year)
150 years
Answer:
0.289792.
Step-by-step explanation:
If we define a month with one or more accident as "success"; and
A month with no accident as "failure" .
- P(one or more accidents will occur during any given month)=0.60.
- P(no accident will occur during any given month)=1-0.60=0.40
We want to calculate the probability that there will be at least four months in which no accidents occur before the fourth month in which at least one accident occurs.
in this case, let k=number of failures before the fourth success
Therefore, 
k follows a negative binomial distribution.
Therefore, the probability is:
![P(k\geq 4)=1-P(k\leq 3)\\=1-\sum_{k=0}^{3}\left(\begin{array}{ccc}3+k\\k\end{array}\right)(0.60)^4(0.40)^k\\=1-(0.60)^4 \left[\left(\begin{array}{ccc}3\\0\end{array}\right)(0.40)^0+\left(\begin{array}{ccc}4\\1\end{array}\right)(0.40)^1+\left(\begin{array}{ccc}5\\2\end{array}\right)(0.40)^2+\left(\begin{array}{ccc}6\\3\end{array}\right)(0.40)^3\right]\\=1-(0.60)^4 \left[ 1+1.6+1.6+1.28\right]\\=1-(0.60)^4[5.48]\\=0.289792](https://tex.z-dn.net/?f=P%28k%5Cgeq%204%29%3D1-P%28k%5Cleq%203%29%5C%5C%3D1-%5Csum_%7Bk%3D0%7D%5E%7B3%7D%5Cleft%28%5Cbegin%7Barray%7D%7Bccc%7D3%2Bk%5C%5Ck%5Cend%7Barray%7D%5Cright%29%280.60%29%5E4%280.40%29%5Ek%5C%5C%3D1-%280.60%29%5E4%20%5Cleft%5B%5Cleft%28%5Cbegin%7Barray%7D%7Bccc%7D3%5C%5C0%5Cend%7Barray%7D%5Cright%29%280.40%29%5E0%2B%5Cleft%28%5Cbegin%7Barray%7D%7Bccc%7D4%5C%5C1%5Cend%7Barray%7D%5Cright%29%280.40%29%5E1%2B%5Cleft%28%5Cbegin%7Barray%7D%7Bccc%7D5%5C%5C2%5Cend%7Barray%7D%5Cright%29%280.40%29%5E2%2B%5Cleft%28%5Cbegin%7Barray%7D%7Bccc%7D6%5C%5C3%5Cend%7Barray%7D%5Cright%29%280.40%29%5E3%5Cright%5D%5C%5C%3D1-%280.60%29%5E4%20%5Cleft%5B%201%2B1.6%2B1.6%2B1.28%5Cright%5D%5C%5C%3D1-%280.60%29%5E4%5B5.48%5D%5C%5C%3D0.289792)
The required probability is 0.289792.
Answer:
c
Step-by-step explanation:
Please see the attached picture for the full solution.
Answer:the height of the balloon is 670.244 feet
Step-by-step explanation:
The right angle triangle BLD represents the scenario.
h represents the height of the balloon.
We would apply trigonometric ratio to determine h.
Tan # = opposite side/adjacent side
Looking at triangle LCD,
# = 61 degrees
h = opposite side
x = adjacent side
Tan 61 = h/x
1.7321 = h/x
h = 1.7321x
Looking at triangle LBD,
# = 54 degrees
h = opposite side
x + 100 = adjacent side
Tan 54 = h/x + 100
1.3764 = h/x + 100
h = 1.3764(x + 100)
Therefore,
1.7321x = 1.3764(x + 100)
1.7321x = 1.3764x + 137.64
137.64 = 1.7321x - 1.3764x
137.64 = 0.3557x
x = 137.64/0.3557 = 386.955
h = 1.7321x = 386.955 × 1.7321
h = 670.244 feet