Directions : Read the following information carefully and answer the following…
2020
Directions : Read the following information carefully and answer the following questions.
Eleven Houses A, B, C, D, E, F, P, Q, R, S, and T are located in a straight row such that the opening gates of some of them opens in north direction and some of them opens in south direction but not necessarily in the same order. No two adjacent houses opening gates opens in the same direction. House B is not located near House A. House Q is located to the immediate left of House B. House P is located fourth to the right of House D, which is located to the immediate left of House R. Number of Houses located to the left of House P is one more than the number of Houses located between House R and House P. Only two houses are located to the left of House A. The number of houses located between House P and House A is one less than the number of Houses located between House T and House C. House T is located near House P. Only one house is located between House F and House Q and the Gates of both of the houses doesn’t open in south direction. Only one house is located between House E and House S, which is not located near House C. House D is 2nd from one of the ends.
How many houses are located to the right of House S?
- A.
One
- B.
Four
- C.
Five
- D.
Three
- E.
Two
Show answer & explanation
Correct answer: D
Concept
This is a facing-direction row puzzle: each house's gate opens north or south, alternating along the row (no two adjacent gates face the same way). Whenever a clue states a house is a certain number of positions ‘to the left/right of’ another house, that left/right must be read in the REFERENCE house's own facing direction — north-facing houses use the standard reading order, but a south-facing house has its own left and right mirrored (like two people facing each other). ‘Between’ and ‘near/adjacent’ clues, by contrast, are always plain physical distance and never flip.
Application
House D is 2nd from one of the ends, so D is at position 2 or position 10.
'House P is fourth to the right of House D' is read in D's own frame. 'House D is immediate left of House R' is read in R's own frame. Testing D = 10 (south-facing, so D's own right points toward LOWER positions) places P at 10-4 = 6, with R (north-facing, standard frame) at 11 -- this keeps the initial D-P-R chain inside the row. D = 2 is ruled out once the remaining houses (Q, B, F) are placed, as the cross-check below confirms.
‘Houses to the left of P’ (P's own frame; P faces south, so P's left is the HIGHER positions) = positions 7-11 = 5 houses. This must be one more than the houses between R(11) and P(6), i.e. positions 7-10 = 4 houses. 5 = 4 + 1, confirmed.
‘Only two houses to the left of House A’ (A's own frame; A faces north, standard) fixes A at position 3.
Houses between P(6) and A(3) = positions 4-5 = 2. This is one less than houses between T and C, so that count is 3. House T is near (adjacent to) House P(6), so T is at position 5 or 7; only T = 5 leaves a valid slot exactly 4 away for C, giving C = 1.
'House Q is immediate left of House B' is read in B's own frame. B faces south, so B's own left is the HIGHER-numbered side, placing Q one position above B (Q = B + 1). With F, Q, B, D, R still to fit into the remaining slots, this pins B = 8, Q = 9.
Only one house lies between F and Q, and both their gates face north (not south): with Q = 9 (north), F must also sit on a north-facing position exactly two away, giving F = 7.
The two positions left over, 2 and 4, must hold E and S with exactly one house between them (positions differ by 2) — satisfied either way — but House S is not near (not adjacent to) House C(1), which rules out S = 2. So S = 4 and E = 2.
The alternating gate pattern anchored by D(10)=south and R(11)=north extends uniquely across the row: positions 1,3,5,7,9,11 face north (C, A, T, F, Q, R) and 2,4,6,8,10 face south (E, S, P, B, D) — every one of the direction-sensitive clues above checks out against this pattern.
The question asks for houses to the right of House S — read in S's OWN frame. Since S faces south, S's own right is the LOWER-numbered side. Positions 1, 2 and 3 (Houses C, E and A) sit on that side, so exactly three houses are to the right of House S.
Cross-check
Re-reading every clue against the final row — C, E, A, S, T, P, F, B, Q, D, R (positions 1-11, gates N,S,N,S,N,S,N,S,N,S,N) — confirms all twelve conditions simultaneously (adjacency, betweenness, and every left/right relation in its reference house's own facing frame). No other placement of D (position 2 instead of 10) keeps the whole chain inside the 11-house row, so the arrangement, and therefore the count of three houses to House S's right, is unique.
Answer: Three.