Q1. [1] § 1.4 Summary
If $x$ is the LCM of 4, 6, 8 and $y$ is the LCM of 3, 5, 7 and $p$ is the LCM of $x$ and $y$, then which of the following is true?
- A $p = 35x$
- B $p = 4y$
- C $p = 8x$
- D $p = 16y$
Previously asked in CBSE board exam
2025 30/3/1 Q2
Generated by claude-sonnet-4-6 · 2026-06-15 10:28 · grounding rag
Model Answer
Option (B): $p = 4y$
$x = \text{LCM}(4,6,8) = 24$; $y = \text{LCM}(3,5,7) = 105$; $p = \text{LCM}(24,105) = 840$.
Check: $4y = 4 \times 105 = 840 = p$. ✓
Explanation
Calculate each LCM by prime factorisation: $8=2^3$ gives $x=2^3\times3=24$; $y=3\times5\times7=105$; $p=2^3\times3\times5\times7=840$. Then verify each option numerically — only $4y$ equals 840. Always compute first, then check options.
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