Answer:
Please check the explanation.
Step-by-step explanation:
We know that when 'y' varies directly with 'x', we get the equation
y ∝ x
y = kx
k = y/x
Here k is called the constant of proportionality.
Taking an example:
For example, let suppose x and y are directly proportional with x = 4 and y = 10.
We can calculate the constant of proportionality using the formula
k = y/x
substitute x = 4, y = 10 in the equation
k = 10/4
k = 2.5
And at x = 5 and y = 12.5
k = y/x
substitute x = 5, y = 12.5 in the equation
k = 12.5/5
k = 2.5
Therefore, we conclude that a constant of proportionality k = 2.5.