Question 914375
Let {{{ d }}} = the one-way distance 
in km  to the village
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Going to the village:
Let {{{ t }}} = time in hrs to go to the village
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{{{ d = 18t }}}
Coming back from village:
{{{ d = 12*( 6.25 - t ) }}}
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By substitution:
{{{ 18t = 12*( 6.25 - t ) }}}
{{{ 18t = 75 - 12t }}}
{{{ 30t = 75 }}}
{{{ t = 2.5 }}}
and
{{{ d = 18t }}}
{{{ d = 18*2.5 }}}
{{{ d = 45 }}}
{{{ 2d = 90 }}}
Total distance traveled is 90 km
check:
{{{ d = 12*( 6.25 - t ) }}}
{{{ 45 = 12*( 6.25 - 2.5 ) }}}
{{{ 45 = 12*3.75 }}}
{{{ 45 = 45 }}}
OK