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Determine P(E|F). Two coins are tossed once, where E: tail appears on one coin, F: one coin shows head

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Question

Determine P(E|F).

Two coins are tossed once, where 

E: tail appears on one coin, F: one coin shows head

Sum
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Solution

S = {HH, TH, HT, TT}

n(S) = 4

E : A coin shows tails,

E = {TH, HT}

P(E) = `1/2`

F: Head appears on a coin,

F = {TH, HT}

P(F) = `1/2`

E ∩ F = {TH, HT}

n(E ∩ F) = 2

P(E ∩ F) = `2/4 = 1/2`

Thus, P(E | F) = `(P(E ∩ F))/(P(F))`

`= (1/2)/(1/2)`

= 1

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Chapter 13: Probability - Exercise 13.1 [Page 539]

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NCERT Mathematics Part 1 and 2 [English] Class 12
Chapter 13 Probability
Exercise 13.1 | Q 7.1 | Page 539

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