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
Answer:
7
3
all real numbers
y>0
Step-by-step explanation:
Just got it right on edge. i got you little bro
Answer:
<em>84%</em><em> of the wage earners earn less than $14,000 each. </em>
Step-by-step explanation:
The Empirical Rule (68-95-99.7%)-
According to this around 95% of the data will fall within two standard deviations of the mean.
As the bell curve is symmetrical, so the remaining 5% will be divided into 2 equal parts. So 2.5% will be above 2 standard deviation and 2.5% will be below 2 standard deviation.
As it is given that, the top 2.5% of the wage earners earn $18,000 or more, so 18,000 is 2 standard deviation away from the mean 10,000.
i.e 

We know that,

where,
X = raw score = 14,000
μ = 10,000
σ = 4,000
Putting the values,

Now, calculating the value from the z score table,

As the probability at
is the area below that, so 84% of the wage earners earn less than $14,000 each.
Answer:
No.
Step-by-step explanation:
18 is less than 21.50 & there is only a one time fee for Shantay’s Shirts.