The 48 flies of them will live longer than 21 days if there are 300 houseflies in the study.
<h3>What is a normal distribution?</h3>
It's the probability curve of a continuous distribution that's most likely symmetric around the mean. On the Z curve, at Z=0, the chance is 50-50. A bell-shaped curve is another name for it.
We have mean u = 18 days
SD = 3 days
X = 21 days
From the formula:
Z = (X - u)/SD
Z = (21 - 18)/3 = 1
P(x<21) = 0.84134
P(x>21) = 1 - P(x<21) = 0.15866
Number of flies = 300×0.15866 = 47.59 ≈ 48 flies
Thus, the 48 flies of them will live longer than 21 days if there are 300 houseflies in the study.
Learn more about the normal distribution here:
brainly.com/question/12421652
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