Medication question

This is simple math. Set up the problem and let us know what you got. You would need a large syringe to fit all the diluent in with the med. But if you look at it, you should be able to do this in your head.

if you just do basic math without any equation set up

100mg/ml for total of 500mg/5ml but you need 20mg/ml

100/20=5. So you would need 100mg/5mL then multiply by 5 to get 500mg/25mL

You have 500mg already but only in 5ml so you need to add 20mL of diluent to get to 25ml total.

And I did the work for you because it was so simple. In most cases, when you have a math problem, people here will require you show your work first. You learn nothing if the work and answer are just given to you.

I know how to do the math, that's what I got my instructor however insisted you add 5mL, which would give you a concentration of 50mg/mL.

Then quite simply, your instructor was wrong. Either that or there was a misread of the dilution requirement of the med by either you or your instructor. Either way, if you pleaded your case and showed the instructor your math, and they insisted on only adding 5mL of diluent, based on what you said about the dilution requirements, the instructor is wrong and thats on them.