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Determine P(E|F). A coin is tossed three times, where E: head on third toss, F: heads on first two tosses

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Question

Determine P(E|F).

A coin is tossed three times, where

E: head on third toss, F: heads on first two tosses

Sum
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Solution

If a coin is tossed three times, then the sample space 'S' is,

S = {HHH, HHT, HTH, HTT, THH, THT, TTH, TTT}

Total sample space = 23 = 8.

E = {HHH, HTH, THH, TTH}

F = {HHH, HHT}

E ∩ F = {HHH}

P(E ∩ F) = `1/8`, P(F) = `2/8 = 1/4`

P(E | F) = `(P(E ∩ F))/(P(F)) = (1/8)/(1/4)`

`= 4/8`

`= 1/2`

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Chapter 13: Probability - Exercise 13.1 [Page 538]

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NCERT Mathematics Part 1 and 2 [English] Class 12
Chapter 13 Probability
Exercise 13.1 | Q 6.1 | Page 538

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