Question 925194
Let {{{ t }}} = the time in hrs she spent traveling
by bus in the 1st case
{{{ 300 - 60 = 240 }}} km = distance in km  traveled
by bus in the 1st case
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The speed of the bus is:
{{{ 240 / t }}} km/hr
The speed of the train is:
{{{ 60/4 = 15 }}} km/hr
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In the 2nd case:
{{{ d/r[1] + d/r[2] }}} = total time of travel
{{{ 100/15 + ( 300 - 100 ) / (( 240/t )) = 4 + t + 10/60 }}}
{{{ 20/3 + 200*( t/240 ) = 25/6 + t }}}
{{{ 40/6 + (5/6)*t = 25/6 + (6/6)*t }}}
{{{ 40 + 5t = 25 + 6t }}}
{{{ t = 15 }}} hrs
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The speed of the bus is:
{{{ 240/t = 240/15 }}}
{{{ 240/t = 16 }}} km/hr
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The speed of the train is:
{{{ 60/4 = 15 }}} km/hr
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check answer:
{{{ 100/15 + ( 300 - 100 ) / (( 240/t )) = 4 + t + 10/60 }}}
{{{ 100/15 + 200 / (( 240/15 )) = 4 + 15 + 1/6 }}}
{{{ 20/3 + 200 / 16 = 19 + 1/6 }}}
{{{ 6 + 2/3 + 25/2 = 19 + 1/6 }}}
{{{ 13 = 12.5 + 4/6 - 1/6 }}}
{{{ 13 = 13 }}}
OK