

Confusing medication calculation formula - Question!
Hi all! This ones been bugging me since last night. 2 entries from Saunders, Comprehensive Review for the NCLEX-RN Examination book.
First calculation, on hand is noted in the question as 10mg, so naturally H is 10
Second calculation, on hand is 0.4 mg (per tablet). But the H in the formula is 1 grain.... Now we know 1 grain is 60mg, but 1 grain is not the "on hand" in the scenario give, but 0.4 mg. So why is 1 grain the H there and why is the vehicle 60 grams when V is "1 tablet"?
Thank you!