Question 444217
Let the total of boys plus girls = {{{x}}}
The number of boys who watch hockey is {{{ .75*(x/2) = .375x }}}
The number of girls who watch hockey is {{{  .65*(x/2) = .325x }}}
The number of students who don't watch hockey is {{{ x - ( .375x + .325x ) = .3x}}}
The number of boys who don't watch hockey is {{{ .25*(x/2) = .125x }}}
The probability that someone who doesn't watch hockey is a boy is
{{{ .125x / .3x = .417 }}}