Question

An airplane flies at 440 miles per hour. How fast is it flying in feet per second?

Answer 1

440 (miles/hr)(1 hr/3600 sec)(5280 ft/1 mile) 
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= (440*1*5280)/(1*3600*1)(ft/sec)

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= 645 1/3 ft/sec

Answer 2

440 (miles/hr)(1hr/36000sec)(5280ft/mile)
(440*1*5280)/(1*3600*1)ft/sec

645 1/3 ft/sec.