An unresponsive 41 lb (18.6 kg) child, with supraventricular tachycardia, is prescribed oral amiodarone 5 mg/kg. it comes as a solution of 150 mg/3 ml. how many milliliters should be given? record your answer using one decimal place.

The answer is 1.9 millimeters. 
Solution
To get the mL value, you have to multiply the following:
(18.6 kg)(5 mg/kg)(3mL/150mg)=mL
The technique here is that you have to think of isolating the unit you are finding and then you have to find a way that you can divide the units until you will find your needed unit. In the solution, you can see that kg/kg=1 and mg/mg=1 so the only unit left is mL. There you can get your answer. Don't be confused by the reciprocal of 150mg/3mL because it is only to get your needed answer.

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