Question 934569
Average speed is always: ( total distance ) / ( total time )
The time for the 1st mile is: {{{ 1 / 15 }}} hrs
Let {{{ t }}} = the time for the 2nd mile in hrs
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You need to solve:
{{{ 30 = ( 1 + 1 ) / ( 1/15 + t ) }}}
{{{ 30 = 2 / ( 1/15 + t ) }}}
{{{ 1/15 + t = 2/30 }}}
{{{ 1/15 + t = 1/15 }}}
{{{ t = 1/15 - 1/15 }}}
{{{ t = 0 }}}
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It is impossible, since the car can't travel the 2nd
mile in zero time