If carrie and cory add on 18% tip to the bill after tax what does their lunch cost in total

The cost of total lunch is 1.18 y ( 1+ 0.0 x )

Step-by-step explanation:

Given as :

The percentage of tip added tot he bill after tax = 18 %

Let the tax added to the bill = x % of total the lunch price

Let The total lunch cost = y

So, The cost of the lunch after tax = y + x %  × y

I.e The cost of lunch after tax = y × ( 1 +x % )

Or. The bill of lunch after tax = y × ( 1 + 0.0 x )

Now the cost of lunch after tax and tip =18 % of y × ( 1 + 0.0 x ) + y × ( 1 + 0.0 x )

Or, the cost of lunch after tax and tip =  y × ( 1 + 0.0 x ) (0.18 + 1 )

∴ The cost of lunch after tax and tip =  y × ( 1 + 0.0 x ) × 1.18

Hence The cost of total lunch is 1.18 y ( 1+ 0.0 x )  Answer