Question 1009622
Let {{{ w }}} = tail wind in mi/hr
Let {{{ s }}} = the plane's speed in still air
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{{{ s + w = 640 }}}
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For this trip:
{{{ 1280 = 640t }}}
{{{ t = 2 }}} hrs
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I'm not sure, but I think that the fact the plane
arrived 8 min early accounts for the tail wind
If so:
{{{ 1280 = s*( 2 + 8/60 ) }}} ( more time without the tail wind )
{{{ s = 1280/2.1333 }}}
{{{ s = 600 }}}
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{{{ s + w = 640 }}}
{{{ 600 + w = 640 }}}
{{{ w = 40 }}}
The wind speed is 40 mi/hr