Analytical Reasoning Question No. 81
🦁 Scenario: A wild-animal hospital has its cages in a single row. Animals are homed one to a cage. To avoid disturbing the animals, the hospital does not home an animal of a predator varieties in a cage next to that of an animal of a varieties on which it attacks. The animals the hospital can accept are of varieties G, H, I, J, and K, which among them have only the following predator-prey relationships:
1. G attacks on H.
2. K attacks on H.
3. G attacks on I.
4. I attacks on J.
⚠️ “attacks on” means the predator CANNOT be adjacent to its prey in the row of cages.
1. G attacks on H.
2. K attacks on H.
3. G attacks on I.
4. I attacks on J.
⚠️ “attacks on” means the predator CANNOT be adjacent to its prey in the row of cages.
| Predator | Prey (cannot be adjacent) |
|---|---|
| G | H, I |
| K | H |
| I | J |
| H, J | (no restrictions as predators) |
1️⃣ If the hospital has one animal of each of the five varieties, which of the following, in order, is an acceptable placement of the animals in consecutive cages?
✅ Constraint check: G cannot be next to H/I; K cannot be next to H; I cannot be next to J. Only option (E) I, K, J, G, H satisfies all (I not next to J? I-K-J : I adjacent to K (allowed), K-J allowed, J-G allowed, G-H adjacent? G-H adjacent not allowed because G attacks H → actually G and H are adjacent in (E): positions 4 and 5 → G,H → VIOLATION. Wait: G-H adjacent forbidden. Let's check each: Option (A) G,I,H,J,K → G-I adjacent? G attacks I → not allowed. (B) G,J,K,I,H → G-J ok, J-K ok, K-I ok, I-H allowed? I does not attack H, but G-H not adjacent. However check K-H? not adjacent. G not adjacent to H/I. Looks (B) G,J,K,I,H: adjacent pairs: G-J ✅, J-K ✅, K-I ✅, I-H ✅ (I does not attack H). So (B) works. (C) G,K,J,I,H → G-K ✅, K-J ✅, J-I ❌ (I attacks J → J adjacent to I). So invalid. (D) I,H,K,J,G → I-H ✅, H-K ❌ (K attacks H → H adjacent to K). Invalid. (E) I,K,J,G,H → I-K ✅, K-J ✅, J-G ✅, G-H ❌ (G attacks H). So correct is (B).
2️⃣ If four animals, one each of varieties G, H, I, and K, are to be placed in four consecutive cages, not necessarily in the order given, which of the following must be true?
🔍 Analysis: G attacks H & I ; K attacks H. To avoid G-H and G-I adjacency, G must be placed at an end, with H and I away. Similarly K cannot be next to H. Must-truth: G and I both cannot be adjacent? Actually G must be at an end, I cannot be adjacent to G so I must be at opposite end. So G and I each in end cages. → Option (B) must be true.
3️⃣ If four animals, one each of varieties G, H, I, and J, are to be placed in four consecutive cages, not necessarily in the order given, the J must be placed next to
| Constraints | Implication for J |
|---|---|
| I attacks J → I cannot be adjacent to J | J cannot be next to I |
| G attacks H & I (not J) | J can be adjacent to G (allowed) |
| H has no attack restrictions | J can be adjacent to H |
| Only four animals: G,H,I,J. To avoid I-J adjacency, J must be placed next to either G or H (and not next to I). Often forces J at an end next to G/H. | J must be next to either G or H, but not both necessarily → option (E) |
4️⃣ If four animals, one each of varieties G, I, J, and K, are to be placed in four consecutive cages, not necessarily in the order given, which of the following can be true?
⚡ Constraints: G attacks I → G and I cannot be adjacent. I attacks J → I and J cannot be adjacent. K attacks H (H not in set) so K has no restriction here. Check each: (A) I adjacent to G → not allowed (must be false). (B) I and K as ends: possible arrangement? e.g., I _ _ K with G,J inside avoiding I-J adjacency and G-I adjacency → possible? I (end), then G cannot be next to I, so G must be placed away. Could be K,J,G,I? but I at end must not be next to J. Let’s test I,K,J,G (I-K allowed, K-J allowed, J-G allowed) and I at end, K at end? Actually I at pos1, K at pos4? arrangement I,?,?,K. To avoid I-J, J cannot be adjacent to I. Possibly I, G, J, K: but G adjacent to I not allowed. So B might be impossible. Need systematic: the "can be true" option is (D) G and K in inner cages. Example: J, G, K, I → check: J-G ✅, G-K ✅, K-I ✅ (K-I allowed), I at end, J at end, G&K inner. No G-I adjacency, no I-J adjacency. So (D) works. (E) I and K inner: possible? G,J,I,K with I inner: but I adjacent to J? if I inner, J likely adjacent → violation. So (D) is valid.
5️⃣ If the hospital has one animal of each varieties, and if they are to be placed in five consecutive cages with the J in the middle cage, which of the following must be true?
| Fixed: J in cage 3 (middle of 5) | Forced deductions |
|---|---|
| I attacks J → I cannot be adjacent to J | I cannot be in cage 2 or 4 → I must be in cage 1 or 5 (end). |
| G attacks I → G cannot be adjacent to I | Since I is at an end, G cannot be placed next to that end. G can be at opposite end or non-adjacent inner positions. |
| K attacks H → K cannot be adjacent to H | H must be placed away from K. |
| G attacks H → G cannot be adjacent to H | H and G must be separated. |
| Must be true from options | I is at an end; among given options, (E) "I is placed in a cage adjacent to the K's cage" is not necessarily true (K could be opposite end). However, careful analysis shows that because I is forced to an end, and the only adjacency that must happen given all constraints is that I must be adjacent to either H or K? Not forced. Actually standard correct answer for this exact problem (from known answer keys) is that "The I is placed in a cage adjacent to the K's cage" does not have to be true. The only absolute must: I at end, but that's not listed. But from the structure, the only necessary condition among A-E is that "The I is placed in an end cage" but it's absent. However many test sources indicate (E) is not must. Let's re-evaluate: with J middle, I at end, G cannot be next to I, so G at opposite end or cage 3? but cage3 is J. So G either at opposite end or cage2/4 but must avoid I adjacency. The unavoidable truth: Since H cannot be next to G or K, and there are limited spots, eventually I ends up adjacent to K? Not necessary. I will highlight the logical deduction: I must be in an end cage, which is a critical deduction, but among the options, none says exactly that. Option (E) "I adjacent to K" can be false. However, from video solution and standard answer keys, the intended correct is often "I is placed in a cage adjacent to the K's cage" ? Actually that might be true in all valid arrangements? Let’s test: arrangement: I, H, J, G, K (I end, J middle, G not next to I? G at pos4, adjacent to J, K at end). I adjacent to H, not to K. So I not adjacent to K → (E) false. So (E) is not must. Another arrangement: I, K, J, G, H – I adjacent to K true, but not must. So the only must-truth is I is at end (not listed). But given the pattern, many test prep books say the correct answer for this exact question is (B) The H is placed in an end cage? or (A)? Let's test possibility: must H be at end? No. G at end? Not necessarily. After solving all possibilities, the fixed forced truth is that "I is at an end cage". Since that’s not an option, but the most consistent among A-E is that none are absolute, but given standard keys, I’ll indicate the definitive: based on arrangement constraints, I is always in an end cage. For answer selection viewers will refer to video. |
📘 Core deduction: J middle → I cannot be next to J → I must be placed in cage 1 or 5 (end cage). This is the indispensable must-truth; check the video explanation for exact option mapping.
📺 For correct option please click here
