Working to ibuprofen question

1. The following example will demonstrate how to perform the calculation but values used are different to those in your question.
Baby E, a 3 month old infant who weighs 6.2 kg, has been prescribed ibuprofen at a dose of 5 mg/kg 4 times a day for 6 days.
Ibuprofen is available as a 100 mg/5 mL oral suspension.
What is the volume, in mL, of the oral suspension that you should supply? Give your answer to one decimal place.
Step 1: Calculate the amount of ibuprofen per dose
The dose is 5 mg/kg and Baby E weighs 6.2 kg. Therefore the amount of ibuprofen is 5 × 6.2 = 31 mg
Step 2: Calculate the amount of ibuprofen required to fulfil the prescription.
Baby E receives 31 mg 4 times a day for 6 days so the total amount of ibuprofen is 31 × 4 × 6 = 744 mg
Step 3: Calculate the volume of solution that contains 744 mg of ibuprofen.
The strength of the solution is 100 mg/5 mL
So there would be 1 mg in 0.05 mL
And 744 mg in 744 × 0.05 mL = 37.2 mL
You should supply 37.2 mL of the oral solution.