mpt · CSS study notes
Comparison
Core Idea
"Who is taller/older/richer than whom" style chains. The skill is combining multiple pairwise comparisons into one consistent ranking, then reading off whatever the question asks (highest, lowest, 2nd highest, etc.)
Common Relationship Types
- Greater than / less than chains (age, height, rank, price)
- Direct comparisons: "A is older than B"
- Indirect/quantified comparisons: "A is twice as old as B", "A is 3 years older than B", "A earns Rs.500 more than B"
- Equal comparisons: "A and B are the same height"
Strategy
- Convert every clue to symbolic form (>, <, =, or a numeric difference) as you read
- Build one master chain/order — don't keep clues as separate mental notes
- For quantified clues ("twice as much", "5 more than"), assign a variable and solve algebraically if exact values are needed
- Double check direction — "A is shorter than B" is easy to misread as the reverse under time pressure
Worked Examples
-
A is older than B. C is younger than D. B is older than D. Order from oldest to youngest.
→ A > B > D > C → A, B, D, C
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Ali earns twice as much as Bilal. Bilal earns Rs.5000 more than Sara. Sara earns Rs.10,000. Find Ali's salary.
→ Sara=10,000; Bilal=10,000+5,000=15,000; Ali=2×15,000=Rs.30,000
-
Among five friends, P is taller than Q but shorter than R. S is the tallest. T is shorter than Q. Who is the shortest?
→ S > R > P > Q > T → T is the shortest
-
X is 4 years older than Y. Y is 2 years younger than Z. If Z is 20, find X's age.
→ Z=20, Y=20-2=18, X=18+4=22
Drill
- A is richer than B. C is poorer than D. B is richer than D. Who is richest? — A
- M is 3 years older than N. N is 5 years younger than O. If O is 30, find M's age. — 28
- In a group, P > Q, R > P, S < Q. Order from greatest to least. — R, P, Q, S
- Company A's revenue is triple Company B's. Company B earns Rs.2 million more than Company C. Company C earns Rs.1 million. Find Company A's revenue. — Rs.9 million
Practice tracker
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