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Determine P(E|F). Two coins are tossed once, where E: no tail appears, F: no head appears - Mathematics

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Question

Determine P(E|F).

Two coins are tossed once, where 

E: no tail appears, F: no head appears

Sum

Solution

S = {HH, TH, HT, TT}

n(S) = 4

E: no tail appears,

E = {HH}

n(E) = 1

P(E) = `(n(E))/(n(S)) = 1/4`

F: no head appears

F = {TT}

n(F) = 1

P(F) = `(n(F))/(n(S)) = 1/4`

E ∩ F = Φ, n(E ∩ F) = 0, P(E ∩ F) = 0

P(E | F) = `(P(E ∩ F))/(P(F))`

`= 0/(1/4)`

= 0

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Chapter 13: Probability - Exercise 13.1 [Page 539]

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NCERT Mathematics [English] Class 12
Chapter 13 Probability
Exercise 13.1 | Q 7.2 | Page 539

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