Dosage Calcplease help!

Hello everyone
I have done nothing all of summer break but now I am worried about my dosage calc tests coming up next week I have always passed them the 1st time, but for some reason I am forgetting how to set these types of problems up, so any help at all would be really appreciated!!!!!!
25 ml of ondansetron 4mg is to infuse at 17 gtt/min using a macrodrip tubing with a drip factor of 10gtt/min. How long will this infusion last?
400 ml of IV solution is in the IV bag when you start your shift at 2300. The infusion rate is 25 ml/hr. At what time will this infusion be completed?
When you begin your shift at 0700, the client's enteral feeding bag contains 240 ml. The physicians' order reads to start enteral feedings at 30ml/hr and q2h increase the feeding by 10 ml until a goal of 80 ml/hr. At what time will this feeding be completed?
Thanks again for any help and good luck to everyone in classes this semester! :spin: 

Aug 18, '06Specialty: med/surg, telemetry, IV therapy, mgmt ; Joined: May '05; Posts: 15,027; Likes: 8,97425 ml of ondansetron 4mg is to infuse at 17 gtt/min using a macrodrip tubing with a drip factor of 10gtt/min. How long will this infusion last?By dimensional analysis: 25mL / 1 (amount to be given, set up as a fraction over the number 1, it's identity) X 1min / 17gtts (infusion rate) X 10gtts / lmL (infusion rate factor of IV tubing) = 14.705min (round off) > 15 min.
400 ml of IV solution is in the IV bag when you start your shift at 2300. The infusion rate is 25 ml/hr. At what time will this infusion be completed?400 mL divided by 25 mL/hr = 16 hours to complete the amount of fluid in the bag. Since 2300 hours is 11pm at night, 11pm + 16 hours = 2pm the next day
When you begin your shift at 0700, the client's enteral feeding bag contains 240 ml. The physicians' order reads to start enteral feedings at 30ml/hr and q2h increase the feeding by 10 ml until a goal of 80 ml/hr. At what time will this feeding be completed?I recommend you make a small chart with the following headings:
time of day /rate of infusion/ times 2 hours/ = / amount infused / = / total amount infused / time of day.
You start out at 0700 at 30ml/hr for 2 hours. So, at 0900 you have given 60mL. At 0900 you increase the rate to 40mL/hr for the next 2 hours. So, at 1100 you have given 80mL more for a total of 140mL (60mL + 80mL). At 1100 you increase the rate to 50mL/hr for the next 2 hours. So, at 1pm you have given 100mL more for a total of 240mL (60mL + 80mL + 100mL) which is all the enteral feeding you have in the bag. So, your final answer is 1pm.

Aug 18, '06Joined: Apr '06; Posts: 2,699; Likes: 7,017"400 mL divided by 25 mL/hr = 16 hours to complete the amount of fluid in the bag. Since 2300 hours is 11pm at night, 11pm + 16 hours = 2pm the next day"
With all due respect, I believe the completion time is actually at 1500 hours (3pm). 
Aug 18, '06Occupation: student Joined: Jun '05; Posts: 72; Likes: 1Thanks so much! Yes you are right, the one is completed at 1500 or 3pm You guys were a big help...Thanks!! :wink2:

Aug 18, '06Specialty: med/surg, telemetry, IV therapy, mgmt ; Joined: May '05; Posts: 15,027; Likes: 8,974Quote from emtb2rnOops! Sorry."400 mL divided by 25 mL/hr = 16 hours to complete the amount of fluid in the bag. Since 2300 hours is 11pm at night, 11pm + 16 hours = 2pm the next day"
With all due respect, I believe the completion time is actually at 1500 hours (3pm).