lawanda and sierra eat dinner

Question

lawanda and sierra eat dinner at a restaurant with a 6% sales tax . They leave an 18% tip on the pre-tax amount of the bill . If they pay a total of 37.20 including tax and tip, what was the pre-tax bill for their meal?

Answer 1

Let x = pre-tax bill

 

"6% sales tax" is 0.06x      [note: 6% can be written as 0.06 or 6/100 as needed by the problem]

"18% tip on the pre-tax amount"     is 0.18x

" pay a total of 37.20 including tax and tip"     means

      37.20    =   pre-tax amount    +    sales tax     +    tip

      37.50    =         x                   +    0.06x         +    0.18x

      37.50  =  1.24x

         x  =  30.24

 

Check:

   Is   37.50  =  30.24  + (0.06)30.24  +  (0.18)30.24     ?

         37.50  =  30.24  +  1.81  +   5.44   ?

         37.50  =  37.49  (items rounded)   ?  yes

Answer 2

Let the pretax bill = x

 

They pay an 18% tax on the pre-tax part, which is 1.18x

 

Then they include the 6% tax on the bill, which is (1.06)(1.18)x

 

 

The equation you end with is

 

1.06(1.18)x = 37.20

 

 

Solve for x.