Which is the least number exactly divisible by 5, 7, 9 and 21?
वह सबसे छोटी संख्या कौन-सी है जो 5, 7, 9 तथा 21 से पूर्णतः विभाज्य (Divisible) है?
Answer और ExplanationAnswer and explanation
Answer: (A) 315
5 = 5, 7 = 7, 9 = 32, 21 = 3 × 7
LCM = 32 × 5 × 7 = 315
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सबसे छोटी संख्या 315 है।
5 = 5, 7 = 7, 9 = 32, 21 = 3 × 7
LCM = 32 × 5 × 7 = 315
✓
The least number is 315.
SMART APPROACH
7, 21 को भाग देता है, तो LCM(5, 9, 21) लो = 5 × 9 × 7 = 315 (21 और 9 में केवल एक 3 उभयनिष्ठ है)।
7 divides 21, so take LCM(5, 9, 21) = 5 × 9 × 7 = 315 (21 and 9 share only one 3).
Source: GD Constable · 18 May 2026 · Shift 1। Solution: Prashant Sir, Vijayastra।Source: GD Constable · 18 May 2026 · Shift 1. Solution by Prashant Sir, from Vijayastra.