Final answer:
To buy a video game for $75 with a sales tax rate of 8.125%, Gregg will need to save $81.09.
Step-by-step explanation:
To calculate the total cost including sales tax, first convert the percent to a decimal by dividing it by 100. In this case, convert 8.125% to 0.08125. Next, multiply the tax rate by the price of the video game: 0.08125 x $75 = $6.09. Finally, add the sales tax to the original price: $75 + $6.09 = $81.09. Therefore, Gregg will need to save $81.09 in order to buy the video game.