Answer:
Answered and explained below
Step-by-step explanation:
A) We are told that frequency of the trait is still 1 in 8. Thus, population proportion; p = 1/8 = 0.125
Sample size; n = 150
Formula for mean is;
μ = np
μ = 150 × 0.125
μ = 18.75
Formula for standard deviation is;
σ = √(np(1 - p))
σ = √(150 × 0.125(1 - 0.125))
σ = √16.40625
σ = 4.05
B) usually, when np ≥ 10 , we make use of normal distribution.
I'm this case, it is 18.75 which is greater than 10.
Thus,we can use a normal model to approximate the distribution.
C) we are told that he found the trait in 22 of the frogs.
Thus;
Proportion is now; 22/150 = 0.1467
This is a higher probability that the initial one of 0.125 and we can say that the trait has become more common.
