First, we need to convert those lbs to kilograms. One kilo is equal to about 2.2lbs, so:
1kg 2.2lbs
x kg 62lbs
x=62lbs*1kg divided by 2.2lbs
x=28.1kg
The dosage is 200mg by kilogram, and the patient weighs 28.1kg, so we multiply:
28.1kg*200=5620mg
Hope that helped!