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Mathematics — CBSE Class 10 board question

Q1. [1]
Given $\text{HCF}(2520, 6600) = 40$, $\text{LCM}(2520, 6600) = 252 \times k$, 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 30/3/1 Q13
Generated by claude-sonnet-4-6 · 2026-06-15 10:29 · grounding rag
Model Answer

Using HCF × LCM = a × b:

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

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

Answer: A) 1650

Explanation

The key property used is: HCF(a, b) × LCM(a, b) = a × b. First find LCM by dividing the product of the two numbers by their HCF, then divide LCM by 252 to get k. Examiners expect the formula to be stated and calculation shown step-by-step.

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