Answer: 0.125 mg per half minute
Step-by-step explanation:
15mg per hour can be written as 15mg/h
To find out how many mg of medication are delivered per half minute you can convert from hour to minutes
There are 60 minutes in 1 hour, so you can use the conversion factor (1h/60 min) and multiply the expression by it
15 mg/h (1h/60min) = 0.25 mg/min
But the question is per half minute so you have to multiply and divide the previous expression by 0.5 (To obtain 0.5 min in the denominator, which is half minute)
Then,
(0.25 mg/min ) (0.5/0.5) = 0.125 mg/ 0.5 min (0.125 mg per half minute)