Answer:
b. Because the probability of being 15 or more correct is 0.0207, it is likely that she is just guessing at the questions.
Step-by-step explanation:
-This is a binomial probability distribution with p=0.5, n=20 and x=15.
The function is expressed as:

We calculate the probability of guessing 15 or more correctly:

The probability of passing, guessing 15+ correctly, is 0.0207. This probability is very low and it is it is likely that she is just guessing at the questions
Answer:
17x-15 ................... I needed to put dots so I can have 20 characters
Answer:
<h2>
The interest ethan will pay is $164.25</h2>
Step-by-step explanation:
To calculate the interest paid by ethan on the borrowed bike using the formula.
Simple Interest = Principal * rate * time/100
Principal = $2,190, rate = 2.5%, time = 3years
On substitution
SI = 

The interest ethan will pay is $164.25
Answer:
Standard error = 0.070
Step-by-step explanation:
Formula for the standard error of the distribution of differences in sample proportions is;
σ_(A - B) = √((p_a^(1 - p_a^)/n_a) + (p_b^(1 - p_b^)/n_b))
We are given;
p_a^ = 0.48
n_a = 80
p_b^ = 0.13
n_b = 66
Thus;
σ_(A - B) = √((0.48(1 - 0.48)/80) + (0.14(1 - 0.13)/66))
σ_(A - B) = √0.00496545455
σ_(A - B) = 0.070