Question 1026217
For the 1st 120 mi, her speed was
{{{ s[1] = 120/4 }}}
{{{ s[1] = 30 }}} mi/hr
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{{{ s[2] = 30 + 10 }}}
{{{ s[2] = 40 }}}
{{{ 280 = 40t }}}
{{{ t = 7 }}}
It takes her 7 hrs to travel the
last 280 mi