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A coin of diameter 'd' is tossed which lands on a square tile of side 'a'. What is the probability that the coin will fall completely within the tile

A. \(\frac{(a−d)^2}{a^2}\)

B. \(\frac{d(2a−d)}{a^2}\)

C. \(\frac{d(2a−d)}{(a−d)^2}\)

D. \(\frac{(a−d)^2}{d(2a−d)}\)

E. \(\frac{(a−d)}{d(2a−d)}\)

If a coin of diameter 'd' lands inside a square of side 'a' then d ≥ a.
Taking d = a and checking options we find that
A is not possible since a - d = 0 which means 'zero' probability. WRONG.
B is possible
C is not possible since a - d = 0, indeterminant case.
D is again similar reasoning as option A.
E is again similar reasoning as option A.

Answer B.
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What about Those cases when the coin will fall purely outside the
tile,doesn't those cases will affect the net total area

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Chetangmat
What about Those cases when the coin will fall purely outside the
tile,doesn't those cases will affect the net total area

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The question does not asks about the areas a coin would cover outside the square. If you consider that scenario then there's no limit, it goes to infinite cases.

Though i personally feel that question needs a bit of refinement. I will wait for someone to chime in and clear the air.
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