Question

Health department lab officials detected 120,000 bacteria on a dessert plate that has a diameter of 6 inches. What's the approximate population density of the bacteria on the dish?

A. 1,062 bacteria/square inch
B. 1,111 bacteria/square inch
C. 12,739 bacteria/square inch
D. 4,246 bacteria/square inch

Answer 1

Option D.

Step-by-step explanation: I Just Took The Test .

Answer 2

The correct answer is option D, the approximate population density of the bacteria in the dish is 4,246 bacteria / square inch

Explanation:

They give us the diameter of the plate, then the first step is to calculate their area.

The area of a circle according to the diameter is:

`A = (\pi)/(4)(d) ^ 2`

Where d is the diameter.

So:

`A = (\pi)/(4)36\\ A = 9\pi\\ A = 28.274.inches ^ 2`

Now, to find the number of bacteria in per square inch, we divide
`(120000)/(28.274) = 4244.132.`

So, the correct answer is option D, the approximate population density of the bacteria in the dish is 4,246 bacteria / square inch