Four houses stand along a straight road that runs east to west. Neel's house is 300 m east of Meera's. Om's house is 500 m west of Neel's. Priya's house is 150 m east of Om's. Whose house is the farthest west of the four?

Put Meera's house at the 0 mark and count east as positive. Neel is at +300. Om is 500 m west of Neel, so Om is at 300 − 500 = −200. Priya is 150 m east of Om, so Priya is at −200 + 150 = −50. Ordered from west to east the houses read Om (−200), Priya (−50), Meera (0), Neel (+300), so Om's house is the westernmost. The trap is Priya's house: it is described by a westward-sounding chain and does lie west of Meera, but it sits 150 m back towards the east of Om.