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Mathematics — CBSE Class 10 board question

Q1. [1]
If $\text{HCF}(2520, 6600) = 40$ and $\text{LCM}(2520, 6600) = 252 \times k$, then the value of $k$ is
  1. (A) $1650$
  2. (B) $1600$
  3. (C) $165$
  4. (D) $1625$
Previously asked in CBSE board exam
2024 30/2/1 Q5
Generated by claude-sonnet-4-6 · 2026-06-15 10:28 · grounding rag
Model Answer

Using HCF × LCM = Product of two numbers:

$$\text{LCM}(2520, 6600) = \frac{2520 \times 6600}{40} = \frac{16632000}{40} = 415800$$

Given LCM = 252 × k, so $k = \dfrac{415800}{252} = 1650$.

(A) 1650

Explanation

The key formula is HCF(a, b) × LCM(a, b) = a × b. Calculate LCM first, then divide by 252 to find k. Examiners expect the formula to be stated and the arithmetic shown step-by-step for full credit even in MCQs if working is required.

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