Answer:
The Constant of Proportionality k is 15.
Step-by-step explanation:
Given:
y varies directly with x .
y = 75 when x = 5
To Find:
Constant of proportionality = k =?
Solution:
y varies directly with x .
i.e. y is directly proportional to x
∴ ![y = k\times x](https://tex.z-dn.net/?f=y%20%3D%20k%5Ctimes%20x)
Where
k = constant of proportionality {Remain Same}
So, we will find constant of proportionality k,
∴ When x = 5 and y = 75 we have
∴ ![75 = k\times 5\\\\k=\frac{75}{5}](https://tex.z-dn.net/?f=75%20%3D%20k%5Ctimes%205%5C%5C%5C%5Ck%3D%5Cfrac%7B75%7D%7B5%7D)
![\therefore k =15](https://tex.z-dn.net/?f=%5Ctherefore%20k%20%3D15)
Therefore the Constant of Proportionality k is 15.