Q&A: practice questions with answers

Concept: $\text{Discount}\%=\frac{\text{MP}-\text{SP}}{\text{MP}}\times 100$.

1. Discount $=2500-1360=$ ₹1,140.
2. $\frac{1140}{2500}\times 100=45.6\%$.

Trick: Divide by 25: $\frac{1140}{25}=45.6$.

Answer: (C) 45.6%

Concept: Equalise decimal places, take LCM of the integers, restore the decimal.

1. $10.80$ and $0.06$ → $1080$ and $6$.
2. LCM$(1080,6)=1080$.
3. LCM $=10.80=10.8$.

Trick: $10.8÷0.06=180$ (whole number), so the larger number itself is the LCM.

Answer: (C) 10.8

Concept: Overall average = total runs ÷ total matches.

1. First 23 matches: $23\times 44=1012$ runs.
2. Next 10: $10\times 14=140$ runs.
3. Average $=\frac{1012+140}{33}=\frac{1152}{33}=34.909\dots \approx 34.91$.

Trick: Deviation method: $44-\frac{10\times 30}{33}=44-9.09=34.91$.

Answer: (D) 34.91

Concept: Sum of exterior angles of any polygon $={360}^{\circ }$; sum of interior angles $=(n-2)\times {180}^{\circ }$.

1. Interior sum $=2\times {360}^{\circ }={720}^{\circ }$.
2. $(n-2)\times 180=720\Rightarrow n-2=4\Rightarrow n=6$.

Trick: Interior sum = $k\times {360}^{\circ }$ gives $n=2k+2$; here $k=2$ → $n=6$.

Answer: (A) 6

Concept: $V=\pi r^{2}h$; new volume factor $=(\text{radius factor}{)}^2\times \text{height factor}$.

1. Radius factor $=0.81$, height factor $=2.22$.
2. ${0.81}^2\times 2.22=0.6561\times 2.22=1.4565$.
3. Increase $\approx 45.65\%\approx 46\%$.

Trick: Successive %: $-19\%$ twice $=-34.39\%$; then $-34.39+122-\frac{34.39\times 122}{100}=45.65\%$.

Answer: (D) 46%

Concept: Draw the path step by step; a right turn while facing south means heading west.

1. 8 km south, right → west 6 km, left → south 5 km.
2. Left → east 6 km (back in line with A), right → south 9 km to P.
3. East–west moves cancel ($6-6=0$); south total $=8+5+9=22$ km.
4. So P is 22 km south of A → drive 22 km north.

Trick: Net displacement = (sum of east − west, sum of north − south).

Answer: (D) 22 km towards north

Concept: Use letter positions (A = 1 … Z = 26) and find the gaps.

1. SV-YD: S→V $+3$, S→Y $+6$, V→D $+8$ (22 + 8 = 30 − 26 = 4).
2. BE-HM: $+3$, $+6$, $+8$; DG-JO: $+3$, $+6$, $+8$.
3. FI-LO: F→I $+3$, F→L $+6$, but I→O $+6$ (not $+8$).

Trick: Write gaps as a triple (+3, +6, +8) for each pair; the one with a different triple is odd.

Answer: (D) FI-LO

Concept: Find the single operation linking the two numbers.

1. $96÷8=12$, $184÷8=23$.
2. $144÷8=18$ ✓; $164÷8=20.5$, $172÷8=21.5$, $130÷8=16.25$.

Trick: Second number = first ÷ 8, i.e. first $=8\times$ second.

Answer: (B) 144, 18

Concept: Fix the definite positions first (counted from the left for north-facing people).

1. 5 people left of B → B is 6th; 5 people right of A → A is 2nd.
2. E is left of D, D left of C, and C is immediately left of F.
3. C–F at 3–4 leaves no room for both E and D before C; so E = 1, D = 3, C = 4, F = 5, G = 7.
4. Order: E A D C F B G → nobody is right of G.

Trick: Place the people with exact positions first; the chain E < D < C-F then fits only one way.

Answer: (B) Zero

Concept: Apply the rule digit by digit: even → +1, odd → −1.

1. 5 6 2 1 8 6 4 3 → 4 7 3 0 9 7 5 2.
2. Count each digit in 47309752: only 7 appears twice; the rest once.
3. So one digit is repeated.

Trick: Equal original digits give equal new digits — the two 6's become two 7's; check others don't collide (5→4 and 4→5 swap, 3→2 and 2→3 swap).

Answer: (D) One

Concept: Draw the least-overlap Venn diagram and test each conclusion.

1. Fans lie inside Lights; Bulbs are kept away from Fans.
2. Lights and Bulbs may or may not overlap (outside the Fans part) → I (No light is a bulb) is not certain.
3. 'No fan is a bulb' converts to 'No bulb is a fan' → II follows.

Yaad rakhein: An E-type statement (No A is B) always converts to No B is A.

Answer: (A) Only conclusion II follows.

Concept: Track each letter position and the number separately.

1. 1st letters: P, S, V, Y, B, E (+3 each, Y→B wraps).
2. 2nd letters: H, K, N, Q, T, W (+3).
3. 3rd letters: Z, C, F, I, L, O (+3).
4. Numbers: $\times 2+1$: $63\times 2+1=127$.

Trick: Numbers 3, 7, 15, 31, 63 are $2^n-1$ → next $2^7-1=127$.

Answer: (A) EWO 127

Concept: Find the rule from HARD - AHRD - DRAH.

1. Step 1: swap the first two letters (HARD → AHRD).
2. Step 2: third term = original word reversed (HARD → DRAH); same for ITEM → METI.
3. DUSK → UDSK (swap) and DUSK reversed = KSUD ✓.

Trick: Check the reverse quickly: WENT reversed is TNEW (not TENW), so A fails.

Answer: (B) DUSK - UDSK - KSUD

Concept: Draw a Venn diagram with Pins common to Bricks and Rulers.

1. Pins lie inside both Bricks and Rulers, so Bricks and Rulers must share the Pins region → 'Some bricks are rulers' follows.
2. Rulers may extend beyond Pins → 'All rulers are pins' does not follow.

Yaad rakhein: Two 'All' statements with the same subject always give 'Some' between their predicates.

Answer: (A) Only conclusion (I) follows.

Concept: Facing north, a left turn means west; trace each turn on a sketch.

1. 9 km north, left → west 4 km, left → south 11 km (now 2 km south of A's level).
2. Left → east 5 km (1 km east of A's line), left → north 2 km → P.
3. P is on A's level, 1 km east of A.
4. To reach A: 1 km to the west.

Trick: Net: north $9-11+2=0$; east $5-4=1$ → P is 1 km east, so go west.

Answer: (A) 1 km to the West

Concept: Look for the pattern Number – Number – Symbol.

1. 2 5 $ → 5 qualifies.
2. 6 3 / → 3 qualifies.
3. 9 3 @ → 3 qualifies.
4. Others fail (e.g. 6 after +, 5 6 6, 9 3 followed by numbers).

Trick: Scan only the numbers that are followed by a symbol, then check the previous element.

Answer: (D) Three

Concept: Each letter moves −3; numbers follow $\times 2-1$.

1. G, D, A, X, U, R; N, K, H, E, B, Y; U, R, O, L, I, F.
2. $11\to 21\to 41\to 81\to 161\to 161\times 2-1=321$.

Trick: Wrap-around: A − 3 = X, B − 3 = Y.

Answer: (D) RYF 321

Concept: Position from left $=\text{Total}-\text{position from right}+1$.

1. Maxi from left $=172-21+1=152$.
2. Han is 61 places to the left → $152-61=91$.

Trick: Convert everything to one end first, then move left (subtract) or right (add).

Answer: (A) 91^st

Concept: Check differences of consecutive terms.

1. Differences: 21, 25, 29, 33 (increase by 4).
2. Next difference $=37$ → $156+37=193$.

Trick: Second differences constant (4) → add the next difference.

Answer: (C) 193

Concept: Facing the centre: a person's right is anticlockwise, left is clockwise.

1. Fix F; I is immediately right of F; E is 3rd to the right of F (F 3rd to left of E).
2. I is 3rd to the right of D → D is 3rd to the left of I.
3. G is not next to F → G sits right of I; then H and O fill the rest with one person between them from O's left: O next to F, H between E and D.
4. From the right of G: E, H, D, then O → 3 persons between.

Trick: Start with the person mentioned most (F/I), then place others by counting.

Answer: (B) Three