Answer:
d = 
Step-by-step explanation:
Given that W varies jointly as L and d² then the equation relating them is
W = kLd² ← k is the constant of variation
To find k use the condition W = 140 when d = 4 and L = 54, thus
140 = k × 54 × 4² = 864k ( divide both sides by 864 )
= k , that is
k = 
W =
Ld² ← equation of variation
Multiply both sides by 216
216W = 35Ld² ( divide both sides by 35L )
= d² ( take the square root of both sides )
d = 
Yes because,
8×1 = 8
8×2 = 16
8×3 = 24
8×4 = 32
8×5 = 40
So 40 is a multiple of 8
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)
Answer:
55.5 B
Step-by-step explanation:
We have the following points of data
48, 49, 50, 51, 54, 55, 56, 58, 60, 62, 63, 63
The median is the data point in the middle (when listed in order)
If we find the middle number we'll see that it's between 55 and 56. When this is the case you find the average of the two numbers (add them and divide by 2)
(55+56)/2=55.5
Answer:
55M
Step-by-step explanation: