CBSE Class 10 Mathematics Basic 2024: question 23(B)
Set in the CBSE Class 10 board exam of 2024, paper 430/1/1, section B, question 23(B), for 2 marks. Try it first; the hints and our step-by-step solution are below.
Q23(B) · 2 marks · Very short answerReal Numbers
Show that is not a prime number.
Source: official question paper from cbse.gov.in (PDF). See it in the full 2024 board paper, set 430/1/1.
Hints
Open one hint at a time and try again before the next.
Hint 1
Look for a factor common to both terms.
Hint 2
After taking 11 out, does the number have factors other than 1 and itself?
Step-by-step solution
Each step shows the marks it earns, as an examiner would award them. Checked by an independent re-solve from the question paper.
- 1 mark
- 1 mark
So the number has factors other than 1 and itself (e.g. 11 and 440); it is a composite number, not a prime.
Answer: , composite, hence not prime.
Where the marks are
- Takes 11 common: (1 mark)
- States it has more than two factors, hence not prime (1 mark)
Revise the chapter
- Chapter: Real Numbers (notes, formulas, where marks are lost and every past question)
- Topic: Fundamental Theorem of Arithmetic
More questions from Real Numbers
- 2024 board paper, set 430/3/1 (Basic), Q23(b) · 2 marksExplain why (7 × 11 × 13 + 2 × 11) is not a prime number.
- 2023 board paper, set 430/2/1 (Basic), Q22(b) · 2 marksShow that (15)^n cannot end with the digit 0 for any natural number 'n'.
- 2026 board paper, set 30/1/1 (Standard), Q3 · 1 markFor any natural number n, 6^n ends with the digit :
The question is transcribed from the official paper; figures are described in words. The solution, hints and chapter tag are ours. Spotted an error? Write tosupport@questionbuddy.in.