Answer:
Mean = 1.42
Variance = 0.58
Step-by-step explanation:
Given: X denote the number of luxury cars sold in a given day, and Y denote the number of extended warranties sold.
Also, joint probability function of X and Y are given.
To find:
mean and variance of X
Solution:
From the given joint probability function of X and Y,
Mean of X:
Variance of X:
![var(X)=E\left [ X^2 \right ]-\left ( E\left [ X \right ] \right )^2\\=\frac{31}{12}-\left ( \frac{17}{12} \right )^2\\=\frac{31}{12}-\frac{289}{144}\\=\frac{372-289}{144}\\=\frac{83}{144}\\=0.58](https://tex.z-dn.net/?f=var%28X%29%3DE%5Cleft%20%5B%20X%5E2%20%5Cright%20%5D-%5Cleft%20%28%20E%5Cleft%20%5B%20X%20%5Cright%20%5D%20%5Cright%20%29%5E2%5C%5C%3D%5Cfrac%7B31%7D%7B12%7D-%5Cleft%20%28%20%5Cfrac%7B17%7D%7B12%7D%20%5Cright%20%29%5E2%5C%5C%3D%5Cfrac%7B31%7D%7B12%7D-%5Cfrac%7B289%7D%7B144%7D%5C%5C%3D%5Cfrac%7B372-289%7D%7B144%7D%5C%5C%3D%5Cfrac%7B83%7D%7B144%7D%5C%5C%3D0.58)
D because 1.29 plus 2.75 is 4.04(the money that he used to make the case) and subtract that with $12 and you get $7.96 as the profit.
D = r• t
reverses the equation so that D and r are on the same side
d/r = t
Sam travels 4 hours at a rate of 50 mph
Answer:
Cartesian Coordinate System
• Also called
rectangular coordinate
system
• x- and y- axes intersect
at the origin
• Points are labeled (x,y)
Polar Coordinate System
– Origin and reference
line are noted
– Point is distance r from
the origin in the
direction of angle θ,
ccw from reference
line
– Points are labeled (r,θ)
Cartesian to Polar Coordinates
• r is the hypotenuse and θ
an angle
θ must be ccw from
positive x axis for these
equations to be vali
Step-by-step explanation:
Answer:
No, 2/3 sqrt(5) k^(11/2)
Step-by-step explanation:
