dosage calculation

Question

give gentamicin to a 2900 gm newborn ivp over 20 minutes. Dosage for newborn is 0.3 mg/kg/dose. Gentamicin Is available in 1 mg/ml vial. How many Ml will you give

Answer 1

2900 g x 1 kg/1000 g = 2.9 kg (weight of child in kg)

0.3 mg/kg x 2.9 kg = 0.87 mg gentamicin needed per dose

1 mg/ml (x ml) = 0.87 mg

x = 0.87 ml is the actual dose required.  Since the 0.3 mg/kg has only 1 significant figure, you can round the answer to 1 ml as the dose that should be given.