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What will be the least number which when doubled will be exactly divisible by 12, 18, 21 and 30?

Correct answer: B. 630

  • A. 196
  • B. 630
  • C. 1260
  • D. 2520Election Officer Mcqs

Explanation

First find LCM(12, 18, 21, 30) = 1260. If the number is n, then 2n must equal the least such common multiple, so 2n = 1260 and n = 630. The likely mistake is choosing 1260, which is the required doubled value, not the original number before doubling.

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