Question 436052
Let {{{t}}} = her time spent on the train
Let {{{d}}} = the distance she travels on the train
Equation for train:
{{{ d = 50t }}}
Equation for bike:
{{{ 13 - d = 15*(24/60 - t) }}}
{{{ 13 - d = 15*( .4 - t ) }}}
{{{ 13 - d = 6 - 15t }}}
By substitution:
{{{13 - 50t = 6 - 15t }}}
{{{ 35t = 13 - 6 }}}
{{{ 35t = 7 }}}
{{{ t = .2 }}}
Now find {{{d}}}
{{{ d = 50t }}}
{{{ d = 50*(.2) }}}
{{{ d = 10 }}}
She rides the train for 10 miles
check answer:
{{{ 13 - d = 15*(24/60 - t) }}}
{{{ 13 - 10 = 15*(.4 - .2) }}}
{{{ 3 = .2*15 }}}
{{{ 3 = 3 }}}