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Find the H.C.F and… (Class 10 Maths SQP 2024-25, Q21A)

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MathsCBSE Class 10 · Standard · Sample paper, session 2024-25 · 2 marks · Very short answer

CBSE Class 10 Mathematics Standard sample paper 2024-25: question 21(A)

From the official CBSE sample question paper for 2024-25, section B, question 21(A), for 2 marks. Try it first; the hints and our step-by-step solution are below.

Q21(A) · 2 marks · Very short answerReal Numbers

Find the H.C.F and L.C.M of and using the Prime factorisation method.

Source: official sample paper from cbseacademic.nic.in (PDF). See it in the full Sample paper 2024-25.

Hints

Open one hint at a time and try again before the next.

Hint 1

Break each number into a product of primes.

Hint 2

For the HCF take the lowest powers of the common primes; for the LCM take the highest powers.

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. ½ mark

  2. ½ mark

  3. LCM = product of the greatest powers of the prime factors

    ½ mark

  4. HCF = product of the smallest powers of the common prime factors

    ½ mark

Answer: HCF = 240, LCM = 1440

Where the marks are

  • Prime factorisation of 480 (½ mark)
  • Prime factorisation of 720 (½ mark)
  • LCM = 1440 (½ mark)
  • HCF = 240 (½ mark)

Revise the chapter

Practise this chapterBoard-style questions from Real Numbers, one at a time, marked against the answer key and marking points.Back to the full paperSample paper 2024-25 (Standard): every question, by section.

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.