Number series – insert the missing term by successive division: 840, ?, 420, 140, 35, 7

Difficulty: Easy

Correct Answer: 840

Explanation:


Introduction / Context:
Look for factor-based decay: consecutive divisions by 1, 2, 3, 4, 5 produce a tidy ladder from the start value.



Observation / Approach:

  • 840 ÷ 1 = 840
  • 840 ÷ 2 = 420
  • 420 ÷ 3 = 140
  • 140 ÷ 4 = 35
  • 35 ÷ 5 = 7


Step-by-Step Solution:
The missing second term equals 840 ÷ 1 = 840.



Verification / Alternative check:
All subsequent divisions neatly match the remainder of the given sequence.



Why Other Options Are Wrong:
Other values break the exact factorial-like division progression and will not land exactly on 420 after the next step.



Common Pitfalls:
Starting the division at 2; the pattern begins with ÷1 to include the repeated 840.



Final Answer:
840

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