If it costs $27,375 to maintain a colony of cats for a year with an average daily census of 25 cats, what is the per diem charge?

To calculate the per diem charge, you begin by determining the total yearly cost and then dividing that by the total number of days the cats are maintained and the number of cats in the colony.

The first step involves recognizing the total annual cost of maintaining the colony, which is given as $27,375. The average daily census shows that there are 25 cats. Since a year has 365 days, the total number of cat-days (the total number of days that all the cats are present) can be calculated by multiplying 25 cats by 365 days:

25 cats × 365 days = 9,125 cat-days.

Next, to find the per diem charge, you divide the total cost by the total number of cat-days:

Per diem charge = Total annual cost / Total cat-days

Per diem charge = $27,375 / 9,125 cat-days ≈ $3.00.

This calculation shows that the per diem charge per cat per day is approximately $3.00, making that the correct choice. Understanding this process helps in accurate budgeting and cost management for maintaining laboratory animal colonies.