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ivolga24 [154]
2 years ago
13

There are 2,100 bacteria in a circular petri dish. The dish has a radius of 40 millimeters. What is the approximate population d

ensity? (Use 3. 14 for π) Area of a circle = πr2 0. 02 bacteria per square millimeter 0. 42 bacteria per square millimeter 2. 39 bacteria per square millimeter 52. 5 bacteria per square millimeter.
Mathematics
1 answer:
Tems11 [23]2 years ago
6 0

Answer:

B) 0.42

Step-by-step explanation:

population density=number of people/square units

we plug in 2,100 for the first one but we don't know the second one for that we need the area which is A=πr^{2} so the radius is 40 millimeters so 40^{2} =1600 1600*π=5024

2,100/5024=0.417 round it up and it is 0.42

so B) 0.42 is the answer

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