50 percent off 285

50% off 285 is 142.5

285 minus 50 percent off is 142.5

The discount itself is 142.5: 285 × 50 ÷ 100 = 142.5. Taking it off 285 leaves 142.5.

Only approximately: 142.5 ÷ 0.5 = 285. The discount is rounded to the cent, so several prices give the same 142.5 — 285 (discount 142.5) and 285.01 (discount 142.51); the paid price alone cannot tell them apart.