Cadet College Petaro Entry Test — Original Sample Paper (Class 8)

Answer Key

Every answer carries its method — read the explanation even for answers you got right.

1. 1. A — "Divides exactly" means a number that is a multiple of BOTH; the smallest such is the LCM. 9 = 3², 12 = 2²·3, so LCM = 2²·3² = 36. (3 isn't a multiple of 9 at all, and 72 and 108 are common multiples — but not the smallest.)
2. 2. B — If 3/5 is 45, then 1/5 is 45 ÷ 3 = 15, and the whole tank is 15 × 5 = 75 litres. Direct check: (3/5) × 75 = 45 ✓.
3. 3. C — The rise and the cut don't cancel because the second 10% is taken on a different base: 500 × 1.1 = 550, then 550 × 0.9 = 495. Net change −1% — a classic two-step pattern.
4. 4. D — Total parts = 4 + 3 = 7, so one part = 84 ÷ 7 = 12 m and the shorter piece = 3 × 12 = 36 m. (12 m is one part, not the piece — a half-finished ratio.)
5. 5. A — Five boys hold 5 × 72 = 360 marks; six boys hold 6 × 74 = 444. The newcomer brought 444 − 360 = 84 marks.
6. 6. B — "Greatest possible equal pieces" asks for the HCF: 63 = 3²·7, 84 = 2²·3·7, common = 3·7 = 21 m. Check: 63 ÷ 21 = 3 and 84 ÷ 21 = 4 pieces exactly.
7. 7. C — Multiply out: 5x − 10 = 3x + 6. Move terms: 2x = 16, so x = 8. Verify in the original: 5(6) = 30 and 3(8) + 6 = 30 ✓.
8. 8. D — The three angles total 180°, so the third = 180 − 95 − 40 = 45°. (35° is the difference of the two given angles — not a triangle rule, just a slip.)
9. 9. A — Perimeter → side first: 96 ÷ 4 = 24 m. Area = side² = 24² = 576 m². (9216 = 96² is the classic trap of squaring the perimeter; 384 m is again the perimeter.)
10. 10. B — Average speed = total distance ÷ total time = (120 + 180) ÷ (2 + 3) = 300 ÷ 5 = 60 km/h. (Averaging the two speeds 60 and 60 happens to agree here, but the rule is totals over totals — it would NOT agree if the halves were unequal.)
11. 11. B — "By + a future point" asks for the future perfect: will have + past participle — the tense of "already done by then".
12. 12. C — Apologize TO a person FOR an offence. Two prepositions, two jobs — swapping them (or using "with") is the standard trap.
13. 13. D — A present-simple active becomes the simple passive: am/is/are + past participle. "The plants" is plural subject, so "are watered"; "being" adds a progressive the original never had.
14. 14. A — A true scientific fact takes the zero conditional: present in both halves — "If you heat ice, it turns into water." "Would turn" belongs to imaginary, not factual, conditions.
15. 15. B — Abundant means existing in large quantity — plentiful. 'Scarce' is its opposite, and the other two don't speak of quantity at all.
16. 16. C — Temporary means lasting only a short time; 'permanent' is the direct opposite. 'Brief' and 'short-lived' are synonyms of 'temporary' disguised as distractors.
17. 17. D — The phrase comes from a peace custom of laying one's weapons in the ground — so it means to make peace and end a quarrel.
18. 18. A — A distance treated as one amount takes a singular verb: "ten kilometres IS not a long distance". Plural-looking subjects that name a single measure stay singular.
19. 19. B — More than one boy owning their bags = plural possessive: apostrophe AFTER the plural s (boys'). 'Boys bags' has no apostrophe; 'boy's bags' would mean one boy's multiple bags.
20. 20. C — Placid means calm, still, unruffled — the sense a lake has when nothing disturbs its surface. Depth, frost and crowds are facts the word itself never states.
21. 21. C — Work = force × distance, measured in joules (J). Newtons measure force and watts measure power — the trap pair in every units question.
22. 22. D — Every plane-mirror image is virtual (light does not actually pass through it), the same size, and left-right reversed. Real images come from optics like lenses that converge light to a point.
23. 23. A — Current is charge in motion, measured in amperes. 'Voltage' pushes the charge, 'resistance' restricts it, 'power' is the rate of energy use — each names a different role.
24. 24. B — Evaporation leaves the solid behind as the water leaves as vapour — the standard recovery for dissolved solids. Filtration and sieving can't take a dissolved substance out (it passes through with the water).
25. 25. C — Condensation reverses evaporation: the gas cools and settles into liquid form. Solid→gas is sublimation; liquid→solid is freezing.
26. 26. D — The kidneys continuously strain the blood and pass the waste out as urine. The lungs remove carbon DIOXIDE, the liver processes chemicals, the pancreas manages digestion sugars — different jobs.
27. 27. A — The small intestine's folded, micro-villae-lined walls are the body's absorptive surface; the stomach digests but doesn't absorb nutrients at scale, and the large intestine mainly absorbs water.
28. 28. B — Osmosis is water diffusing across a membrane from where it is more concentrated to less — exactly the gradient root cells set up relative to soil water.
29. 29. C — Conduction is heat travelling PARTICLE to particle through a solid — the soup heats the spoon's first particles and the vibration walks up the handle. Convection needs a moving fluid; radiation works across empty space.
30. 30. D — Exothermic processes RELEASE heat: burning paper gives flame — the hallmark of combustion. Melting, boiling and evaporation are endothermic: they take heat in, which is why water cools the surface it evaporates from.
31. 31. D — 'کہانی' مؤنث لفظ ہے۔ مؤنث الفاظ کی خالص جمع عموماً 'یاں' کے اضافے سے بنتی ہے۔ 'کہانیوں' اضافی جمع ہے (جیسے: کہانیوں میں)، اور 'کہانیان' نادر صورت ہے۔
32. 32. A — 'درد' کا مطلب تکلیف ہے، جیسے 'دردِ دل'۔ 'خوشی' اس کا متضاد ہے، اور 'شفائی' اور 'دعا' بے تعلق آپشن ہیں۔
33. 33. B — 'شکر' کا مطلب تشکر ہے، اس کا براہِ راست متضاد 'نا شُکری' ہے۔ 'صبر' ایک الگ خوبی ہے جس کا شکر سے متضاد رشتہ نہیں۔
34. 34. C — یہ محاورہ انتہا کی شرمندگی کا اظہار ہے — جیسے کسی کی حقیقت آشکار ہو جائے اور وہ ذلیل ہو جائے۔
35. 35. D — اس محاورے کا مطلب ہے کوشش ناکام رہ جانا — طرح طرح کی کوشش کے باوجود کوئی کام نہ بننا۔
36. 36. A — Fasting in Ramzan is the pillar called Sawm — 'to abstain'. The five pillars name five duties: Salat (prayer), Sawm (fasting), Zakat (alms), Hajj (pilgrimage) and the Kalima (faith).
37. 37. B — Zakat — 'purification' — is the duty of giving a fixed share of saved wealth to those who need it, purifying the remaining wealth and its owner alike.
38. 38. C — The revelation ran through the whole prophetic mission: roughly 13 years in Makkah and about 10 in Madinah — about 23 years in all. (13 and 10 are the two halves; neither is the whole.)
39. 39. D — Before prophethood the Makkans called him Al-Ameen — the trustworthy one — for his known honesty, notably in the caravan trade he managed for Khadija رضی اللہ عنہا.
40. 40. A — Uhud is a mountain just NORTH of Madinah; the battle in 3 AH took place there against the Quraysh. Khyber is a later campaign (7 AH), and Makkah/Ta'if are well south of Madinah.
41. 41. B — Each term doubles the one before: 3 → 6 → 12 → 24 → 48. (30 and 36 are guesses from an adding-steps pattern, and 46 slips a digit — run the doubling once more on your answer before you circle it.
42. 42. C — The gaps grow by 2 as they walk: +3, +5, +7, +9, next +11 → 26 + 11 = 37. Equivalently each term is n² + 1 (1²+1=2, 2²+1=5 … 6²+1=37).
43. 43. D — The first three are flat (two-dimensional) figures; a cube is solid (three-dimensional) — the only item from a different dimension of shape.
44. 44. A — A thermometer measures temperature; a barometer measures ATMOSPHERIC PRESSURE. Height is an altimeter's job; the other two are things the meter reads indirectly at best.
45. 45. B — The sailor PROFESSIONALLY drives the ship; the pilot professionally drives the plane. A passenger rides; an engineer builds or maintains.
46. 46. C — Check the given pair first: C→D, A→B, M→N, P→Q, U→V, S→T — every letter moves ONE step forward. Apply the same rule to EXAM: E→F, X→Y, A→B, M→N, giving FYBN. The distractor that shifts only the first three letters stumbles at the last — verify the rule on the example, then apply it to every letter.
47. 47. D — The potato, carrot and radish are all underground vegetables (roots or tubers); the mango grows on a tree and is a fruit by its family. The list tempts by all being "foods we eat" — the oddity lives below ground.
48. 48. A — The dial is a full circle of 360° split by 12 hour-marks, so each hour-gap is 30°. At 3:00 the hands are 3 gaps apart: 3 × 30° = 90°.
49. 49. B — Draw it: the two diagonals cross at the centre and make 4 small triangles. Joining any two adjacent smalls makes 4 larger triangles (the four "halves" of the rectangle). Nothing larger combines three smalls. 4 + 4 = 8 — the classic panic answer 16 double-counts.
50. 50. C — Each term is halved: 64 → 32 → 16 → 8 → 4. (Halving, not subtracting: the gaps shrink 32, 16, 8 — the difference halving is the halving signature.)