Multiple choice general knowledge math & puzzles

a 101 digit number has 50 2's in the begining and 50 3's at the end 222222....?.....33333 this nos is divisible by 7 find the 51st nos

  1. 2

  2. 3

  3. 5

  4. 7
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This is a divisibility problem involving a 101-digit number with 50 twos, then one middle digit, then 50 threes. For such a number to be divisible by 7, the middle digit must be 5. This follows from the mathematical property that 222...25333... (with equal counts of 2s and 3s) is divisible by 7.

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