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Zina [86]
2 years ago
5

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)
Mathematics
2 answers:
pochemuha2 years ago
6 0
A petri dish is simply a circle; thus, we use the formula of the area of the circle which is <span>πr^2. 
Given r = 40 mm
A = </span>π(40)^2 = <span>5026.55 sq. mm
</span>
Population density = bacteria count / area
PD = 2,100 / <span>5026.55
PD = </span><span>0.417782 bacteria / mm sq.

Therefore, the answer is approximately 0.418 </span><span>bacteria per square millimeter.</span>
saul85 [17]2 years ago
3 0
Determine the area of the circular petri dish through the equation, A = <span>πr^2. Substituting the radius to the equation and solving for area gives, 5024 mm^2. The population density is obtained by dividing the population with the calculated area. Thus, the population density is approximately 0.418 bacteria per mm^2. </span>
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