Home / Topic / Number Properties
Topic Number Properties
Asked 2 times across 2 UPSC exams over 9 years (2015–2024), peaking in 2015.
Key insights
- Most tested in EPFO — 1 of 2 PYQs
- Most asked in 2015
- Recurs across 2 years (2015–2024)
How it travelled across exams
First appearance in each exam — the same idea, reframed.
EPFO 2015 → ESE 2024
How the concept evolved
Long-running — most appearances (1 of 2) predate 2016, and it still returns.
Sample questions
You've seen the pattern — here are a few of the actual PYQs.
ESE2024
Select a two-digit number between 50 and 100. Add 83 to your number. From this number form a new number by adding the digit in the hundreds place to the number formed by the other two digits (the digits in the tens place and the ones place). Now subtract this newly formed number from your original number, to arrive at the final result. What is the final result?
- A 16 ✓
- B 26
- C 36
- D 46
✓ Correct answer: (A)
Quantitative Aptitude › Number System
EPFO2015
If the difference of two numbers is greater than the sum of the numbers, then
- A Both the numbers are negative
- B Exactly one of the numbers is negative
- C At least one of the numbers is negative ✓
- D None of the above
✓ Correct answer: (C)
Quantitative Aptitude › Number System
Study how UPSC repeats — not just the papers
₹199 / 1 year · Founding Member
Full access unlocks the three things no PYQ PDF gives you:
① Cross-exam learning — see the same idea recur across CSE, CAPF, CDS and NDA.
② Topic evolution — how each idea is framed, year by year.
③ Question intelligence — every PYQ + answer, linked to related concepts and similar questions.
e.g. Round Table Conference: CDS 2017 → CSE 2017 → … → CAPF 2024
15 days free, no card required — then ₹199 for 1 year.
Start your 15-day free trial →