Question 1024531
The perimeter is:
{{{ P = 2*90 + 2*70 }}}
{{{ P = 180 + 140 }}}
{{{ P = 320 }}} m
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His speed is:
{{{ 4000 }}} m/hr
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5 rounds is:
{{{ 5*320 = 1600 }}} m
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{{{ d = r*t }}}
{{{ t = d/r }}}
{{{ t = 1600 / 4000 }}}
{{{ t = .4 }}} hrs
Convert to minutes:
{{{ .4*60 = 24 }}}
He takes 24 min to make 5 rounds