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# A prescription calls for 25mg of a medication t.i.d. for 7 days. The stock solution is composed of a 100mg/3mL. How many Liters of the stock solution is needed for the order?

Question:

A
0.01575

Explaination

The abbreviation t.i.d. means 3 times a day. So 7 days x 3 times per day x 25 mg each = 525 mg total needed.

100/3 = 525/x

Cross multiply to solve for x:

100x = 1575

x = 15.75 mL.

The answer asks for liters so divide by 1000:

15.75/1000 = 0.01575 L

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