Problem Solving (PS) | At the rate of l liters per s seconds, how many kiloliters (1000 liter

1 hr= 60 min, 1 min=60 sec
Therefore 1 hr=60*60=3600 sec

Rate is L liters per S seconds
therefore Rate in liters per hour is 3600 L/hr
And finally Rate in kilo liters per hour is 3600 KL/1000 hr

Therefore in x hours, 3600xL/1000s blood will be pumped. hence Option A.

Kudos if it helps.

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