Answer: The expected waiting time is 
Step-by-step explanation:
Since we have given that
Average waiting time for slow elevator = 3 min
Average waiting time for fast elevator = 1 min
probability that a person choose the fast elevator = 
Probability that a person choose the slow elevator = 
So, the expected waiting time would be
![E[x]=\sum xp(x)=3\times \dfrac{1}{3}+1\times \dfrac{2}{3}\\\\=1+\dfrac{2}{3}\\\\=\dfrac{3+2}{3}\\\\=\dfrac{5}{3}\\\\=1\dfrac{2}{3}\ min](https://tex.z-dn.net/?f=E%5Bx%5D%3D%5Csum%20xp%28x%29%3D3%5Ctimes%20%5Cdfrac%7B1%7D%7B3%7D%2B1%5Ctimes%20%5Cdfrac%7B2%7D%7B3%7D%5C%5C%5C%5C%3D1%2B%5Cdfrac%7B2%7D%7B3%7D%5C%5C%5C%5C%3D%5Cdfrac%7B3%2B2%7D%7B3%7D%5C%5C%5C%5C%3D%5Cdfrac%7B5%7D%7B3%7D%5C%5C%5C%5C%3D1%5Cdfrac%7B2%7D%7B3%7D%5C%20min)
Hence, the expected waiting time is 
Step-by-step explanation:
x+100°=180°{being straight angle}
x=180-100
x=80°
again,
45°+x+y=180°{sum of angle of triangle}
45+80+y=180
y=180-125°
y=55°
hope it helps.
Answer:
The line segment 7 cm long is shown below.
Step-by-step explanation:
First we draw a line line segment whose length is 7 cm long. Then we divide the line in small parts.
The length of each part is 1 cm.
Six points on the line segment divides the line in 7 equal parts and length of each part is 1 cm.
From the figure it is noticed that we have total 7 small parts and length of each part is 1 cm. So length of 7 parts is

Hence the total length of line is 7 cm.
Answer:
A.
Step-by-step explanation:
profit=f(x)
so solve for f(x)=1000
1000=70n-400
add 400 to both sides
1400=70n
divide both sides by 70
20=n
20 students need to be enrolled to make a profit of 1000.00