[peaktime]

if you take the aspect ratios based on pixels and multiply by their pixel aspect ratios, both systems have the same aspect ratio. (the final numbers should be closer but these were done using rounded numbers)

NTSC Standard: 720 / 480 = 1.5 x .9 = 1.35

NTSC Widescreen: 720 / 480 = 1.5 x 1.21 = 1.815

PAL Standard: 720 / 576 = 1.25 x 1.09 = 1.3625

PAL Widescreen: 720 / 576 = 1.25 x 1.45 = 1.8125