Question 1184301
Correct option is:{{{2/5}}}
 

Let {{{F }}}denotes fair coin.
{{{T }}}denotes two headed,
{{{H}}} denotes head occurs

{{{P(F)= 3/4}}}

 {{{P(T)=1-3/4= 1/4}}}
 
{{{P(T/H)=  (P( H/T )*P(T)) /(P(H/T)*P(T)+P(H/F)*P(F))}}}.......(By Baye's theorem)   

= {{{(1*(1/4))/(1*(1/4)+(1/2 )*(3/4 ))}}}

= {{{(1/4)/(1/4+3/8 )}}}

= {{{(1/4)/(5/8 )}}}

= {{{8/(4*5 )}}}

={{{ 2/5 }}}