If you pay $22.90 for a DVD that includes a 7% sales tax, what is the price of the DVD before the sales tax?

A) $23

B) $21.40

C) $25

D) $20.50

Let Price before sales Tax is = x

price after slaes Tax is  = x + 7% = x + 0.07x= 1.07x

According to Given condition: 1.07x = $22.90

                                                              x = 20.40