Answer:
10
Step-by-step explanation:
If there is a direct relation between two variables x and y then it can be represented as
y = kx ,
where y is dependent variable
x is independent variable
k is constant of variation
_____________________________
First condition
y = 400
x = r
using y = kx then relationship will be
400 = kr
finding k here
k = 400/r
Second condition
y = r
x = 4
using y = kx then relationship will be
r = 4k
finding k
k = r/4
since in both condition equation is same
thus, value of k will also be same
thus,
400/r = r/4
=> 400*4 = r*r
=> 1600 = r^2

Thus, 40 is the value of r
k = r/4 = 40/4 = 10
Thus, constant of variation is 10 which is correct choice.
To cross validate
k = 400/r = 400/40 = 10
The Mean = (135 + 71 + 69 + 80 + 158 + 152 + 161 + 96 + 122 + 118 + 87 + 85 ) : 12 = 111.166
The smallest value : 69
The greatest value : 161
s² = ∑( x i - x )² / ( n - 1 )
s² = ( 568.274 + 1613.3 + 1777.97 + 971.32 + 2193.42 + 1667.4 + +2483.42 + 230 + 117.38 + 46.7 + 584 + 684.66 ) : 11
s² = 1176.1676
s = √s² = √1176.1676
s ( Standard deviation ) = 34.295
All the values fall within 2 standard deviations:
x (Mean) - 2 s and x + 2 s
114
1^3 + 1^3 + 4^3 = 1 + 1 + 64 = 66
99 - 66 = 33
33/3 = 11
1 + 1 = 2
I am not sure of the exact way to solve this....I just did it by trial and error
Answer:
6.00
Step-by-step explanation: