A city has a 5% sales tax. Is there a proportional relationship between the cost of items before tax and the cost of items after tax?

Yes or No

Yes,

There is a direct proportional relationship between the cost of items before tax and the cost of items after tax.

Step-by-step explanation:

Given - A city has a 5% sales tax.

To find - Is there a proportional relationship between the cost of items

              before tax and the cost of items after tax?  

Proof -

Yes, cost of items before tax is directly proportional to cost of items after tax.

Reason -

With the increase in the sales tax, there is increase in the cost of items after tax, therefore, there is a direct relation between cost of items before tax and cost of items after tax.