Question
A number '71945b' is divisible by 6, but not by 5. What is
the value of (b² + 1)?Solution
ATQ,
Sum = 7 + 1 + 9 + 4 + 5 + b = 26 + b
We want (26 + b) divisible by 3 and b even (for divisibility by 2), and ≠ 0 or 5.
Try b = 4 → 26 + 4 = 30
So, b = 4
(b² + 1) = 16 + 1 = 17
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