the common fruit fly is the most studied organism in genetic research because it
ID: 3207860 • Letter: T
Question
the common fruit fly is the most studied organism in genetic research because it is small, is easy to grow, and reproduce rapidly. the length of the thoras (where the wings and legs attach) in a population of male fruit flies is approximately Normal with mean 0.800 milimeters (mm) and standard deviation 0.078 mm
a.) what proportion of flies have thorax lengths less than 0.6mm?
b.) what proportion have thorax length greater than 0.9mm?
c.) what proportion have thorax length between 0.6mm and 0.9mm?
Explanation / Answer
We are given,
Mean = 0.8
Standard deviation = 0.078
Z = (x – Mean)/Standard deviation
z = (0.6 – 0.8)/0.078
= -2.56
P (z < -2.56)
Now by using Normal Distribution Table we get
P (z<-2.56) = 0.0052
Answer: 0.0052
z = (0.9 – 0.8) /0.078
= 1.28
P ( z >1.28 ) = 1 – P ( z < 1.28 )
By using Normal Distribution Table we get,
P ( z <1.28 ) = 0.90
P (z >1.28 ) = 1 – 0.90 = 0.10
Answer: 0.10
z-score for 0.6 = -2.56 (got in part a)
z-score for 0.9 = 1.28 (got in part b)
P (-2.56 < z < 1.28)
= P (z<1.28 ) – P (z<-2.56)
= 0.90 – 0.0052
= 0.8948
Answer: 0.8948
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.