To find the answer to this question we can take the original cost of the toothbrush ($48) and multiply it by .39 (the decimal version of 39%). Doing so gives us a number of 18.72. This number represents 39% of $48. To find the final cost, we need to deduct the 18.72, which represents the 39% off, from the initial $48 price which equals 29.28. The sale price of a $48 toothbrush that is 39% off will cost $29.28