The houses of A and B face each other on a road going north-south, A’s being on the western side. A comes out of his house, turns left, travels 5 km, turns right, travels 5 km to the front of D’s house. B does exactly the same and reaches the front of C’s house. In this context, which one of the following statements is correct?
- A.C and D live on the same street.
- B.C’s house faces south.
- C.The houses of C and D are less than 20 km apart.
- D.None of the above
▶ Answer & Explanation
Correct answer: D. None of the above
A starts on the west side facing north. Turning left means turning west, traveling 5 km, and then turning right (north) to reach D's house. B starts on the east side facing south. Turning left means turning east, traveling 5 km, and then turning right (south) to reach C's house. This means C and D are on opposite sides of the road, and D is 5 km west and C is 5 km east. Their houses are separated by the north-south road. C's house faces north. The distance between C and D is a minimum of 10 km (across the road, assuming no lateral displacement on the road itself) plus any north-south displacement. Thus, C and D do not live on the same street, C's house faces north, and they could be more than 20 km apart.
Source: UPSC csat 2011