Math:
Well, you know that 12 inches goes into 1 foot.
So, let's start with just making everything into inches.
4 feet * 12 = 48+2 = 50 inches.
3*12 = 36 inches + 7 = 43 inches.
50 - 43 = 7.
Your answer:
7 inches.
Hello! The y-intercept is (0, 4), because the line crosses 0 in the x-axis at that point. We can cross out C and D, because those don't show that. The slope is rise/run. You would go up 3, and go to the right once. If you need to, solve for slope by doing y2 - y1/ x2 - x1. Let's use the point (0, 4) and (1, 7) as an example. We would set it up like this: 7 - 4 / 1 - 0. Solving that would give us 3/1 or just simply three. The slope is positive 3 and the y-intercept is (0, 4). The answer is A.
Answer:
x= -2 and y= 3
Step-by-step explanation:
since x = 2y -8, substitute this in the first equation
Thus, -3(2y-8) + 2y =12
-6y+24+2y=12
-6y+2y=12-24
-4y=-12
y=3
put the value of y in the second equation,
x=2y-8
x=2(3)-8
x=6-8
x=-2
So, x=-2. y=3
Answer:
51/4
Step-by-step explanation:
To begin with you have to understand what is the distribution of the random variable. If X represents the point where the bus breaks down. That is correct.
X~ Uniform(0,100)
Then the probability mass function is given as follows.
Now, imagine that the D represents the distance from the break down point to the nearest station. Think about this, the first service station is 20 meters away from city A, and the second station is located 70 meters away from city A then the mid point between 20 and 70 is (70+20)/2 = 45 then we can represent D as follows
Now, as we said before X represents the random variable where the bus breaks down, then we form a new random variable 
, 
is a random variable as well, remember that there is a theorem that says that
![E[Y] = E[D(X)] = \int\limits_{-\infty}^{\infty} D(x) f(x) \,\, dx](https://tex.z-dn.net/?f=E%5BY%5D%20%3D%20E%5BD%28X%29%5D%20%3D%20%5Cint%5Climits_%7B-%5Cinfty%7D%5E%7B%5Cinfty%7D%20D%28x%29%20f%28x%29%20%5C%2C%5C%2C%20dx)
Where 
is the probability mass function of X. Using the information of our problem
![E[Y] = \int\limits_{-\infty}^{\infty} D(x)f(x) dx \\= \frac{1}{100} \bigg[ \int\limits_{0}^{20} x dx +\int\limits_{20}^{45} (x-20) dx +\int\limits_{45}^{70} (70-x) dx +\int\limits_{70}^{100} (x-70) dx \bigg]\\= \frac{51}{4} = 12.75](https://tex.z-dn.net/?f=E%5BY%5D%20%3D%20%5Cint%5Climits_%7B-%5Cinfty%7D%5E%7B%5Cinfty%7D%20%20D%28x%29f%28x%29%20dx%20%5C%5C%3D%20%5Cfrac%7B1%7D%7B100%7D%20%5Cbigg%5B%20%5Cint%5Climits_%7B0%7D%5E%7B20%7D%20x%20dx%20%2B%5Cint%5Climits_%7B20%7D%5E%7B45%7D%20%28x-20%29%20dx%20%2B%5Cint%5Climits_%7B45%7D%5E%7B70%7D%20%2870-x%29%20dx%20%2B%5Cint%5Climits_%7B70%7D%5E%7B100%7D%20%28x-70%29%20dx%20%20%5Cbigg%5D%5C%5C%3D%20%5Cfrac%7B51%7D%7B4%7D%20%3D%2012.75)
