Answer:
Step-by-step explanation:
The direct variation between any two variables x and y is represented by
y = kx where k is the constant of proportionality.
In the problem given above
Let cost price be y as it depends upon the value of copies
and x be the number of copies of art work
Thus we have equation
Y = kx
it is given that it costs her $1 to make 5 copies, so plugging in the value of x as 5 copies any y as $1 we have
1 = k5
k = 1/5
Thus equation is y = (1/5) x.
To check the validity of equation lets put next set of values value of x as 25 copies , value of y should come as $5.
y = (1/5) 25
y = 5
As we can see that $5 is the value when put x as 25.
Thus our equation y = (1/5) x is correct one.
