alleryIf the number x3339 is divisible by 11, what is the digit x?
A2
B4
C5
D3
Answer & Solution
Correct answer: C. 5
1. Divisibility by 11: (sum of digits at odd places) - (sum at even places) is a multiple of 11.
2. For x3339, from the right: odd places 9, 3, x; even places 3, 3. Odd sum = 12 + x, even sum = 6.
3. Difference = 6 + x. For divisibility, 6 + x = 11, so x = 5.
_Source: RRB Group D CEN-02/2018 PYQ, Q.71._
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