Error on official HESI Practice Question?

[Aedyl]

This is the question sample on the official HESI practice exam from the evolve.elsevier.com website:

A nurse is reviewing the daily intake and output (I&O) of a patient consuming a clear diet. The urinary drainage bag denotes a total of 1,000 mL for the past 24 hours. The total intake is:

2 8-oz cups of coffee

1 16-oz serving of clear soup

1 pint of water consumed throughout the day

How much is the deficit in milliliters? (Enter numeric value only. If rounding is necessary, round to the nearest whole number.)

I answered "440" which was marked as "incorrect". The "correct" answer is 420. I don't understand where that number is coming from, considering that I used the official practice Hesi asses book's (edition 4) conversion chart.

The conversions I used were:

1 cup=8oz

1 oz=30mL

1pt=2 cups

Eventually, I added 480 mL three times and then got my answer of 1440mL and then subtracted 1000 mL from that number.

Where does 420 come from as the answer??? Was the question based on a non-rounded conversion equation?

[Rose_Queen, BSN, MSN, RN]

The exam is likely using the more accurate 29.5735mL/oz conversion, because I get 420 with that factor.

[Aedyl]

The exam is likely using the more accurate 29.5735mL/oz conversion, because I get 420 with that factor.

Will that be used on the actual HESI test instead of 30 mL/oz? I dont think it is fair and honest for the actual HESI Assesment book I ordered to not include the conversion used in the Practice Hesi exam.

[meanmaryjean, DNP, RN]

Will that be used on the actual HESI test instead of 30 mL/oz? I dont think it is fair and honest for the actual HESI Assesment book I ordered to not include the conversion used in the Practice Hesi exam.

You should know the conversion or look it up. "Not fair" will not get you far in life.

[puravidaLV]

Welcome to HESI/ATI you catch the mistakes and they never fix them. I'm fairly certain there are still errors in the ATI books stating smoking is a healthy option for pregnant men.

[chare]

Welcome to HESI/ATI you catch the mistakes and they never fix them...

Again, this is not an error. Forty-eight oinces, multiplied by 29.5735 mL/ounce is 1419.528 ounces. The error was made by yhe OP in her choice to use the more convenient 30 nL/ounce conversion.

OP, in my opinion, when doing any calculations (conversions, dosing calvulations, etc.), always use the most detailed conversion factor available, and never round your results until you have completed all calculations. While not doing so with adults will likely not matter, it can be clinically significant if you work with neonatal or pediatric patients.

[FolksBtrippin, BSN, RN]

Well that is tricky. Don't sweat it too much though. The actual tests are generally non-ambiguous.

But look at this, you learned something. Think of everything you're doing right now as an opportunity to learn, not a score or a chance to prove what you already know, and you will go far.

[Aedyl]

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