Question

Martha paid $42.40 for her sisters birthday present. This included 6% sales tax. What was the cost of the gift before tax?

Answer 1

It's $40.00 

1.06x=42.20 
x=42.40/1.06 
x=40.00

Answer 2

Answer:   The exact answer is: $ 39,856 approaching: $ 40.00

Explanation:  

First,  the value of the sales tax corresponding to 6% is determined:             $ 42.4  x  0.06  =  $  2,544

Now subtract $ 2,544 from the total value of the purchase

               $ 42.4 - $ 2,544 = $ 39,856 approx. $ 40.00 this is the value of the pre-tax gift