198 ml of saline have been administered already.
To calculate the amount of saline administered, we need to consider the following information:
Total volume: 1200 ml
Rate: 2 hourly, meaning 1200 ml is administered in 2 hours.
Time elapsed: 20 minutes
Step 1: Convert minutes to hours
First, we need to convert the time elapsed from minutes to hours:
20 minutes / 60 minutes/hour = 0.33 hours
Step 2: Calculate the amount of saline administered per hour
Divide the total volume by the rate per hour:
1200 ml / 2 hours = 600 ml/hour
Step 3: Calculate the amount of saline administered over 20 minutes
Multiply the hourly rate by the time elapsed:
600 ml/hour * 0.33 hours = 198 ml
Therefore, 198 ml of saline have been administered already.