You Receive A Prescription For Metronidazole 250mg/5ml Liquid 240ml. You Find That You Will Have To Compound This Using 500 Mg Tablets. How Many Tablets Will Be Needed To Fill This Order Completely?

The mass of Metronidazole you need is (240 ml)*(250 mg/5 ml) = 48*(250 mg)

The number of tablets needed is (the total mass)/(mass/tablet)
 = (48*250 mg)/(500 mg/tablet) = 48*(250/500) tablets = 24 tablets.