Approximately 15% of Americans have a blood type of B. The local blood bank has 80 donors stop by on a given day (which can be considered a random sample from the population). What is the probability that between 15% and 20% of the donors on a given day have a blood type of B?

the probability that between 15% and 20% of the donors on a given day have a blood type of B is 0.3944

Step-by-step explanation:

Given that;

Binomial Distribution

n = 80

p = 0.15

q = 1 - p = 0.85

Mean = μ = np = 80 X 0.15 = 12

SD = σ = √(npq) = √(80 x 0.15 x 0.85) = -3.1937

Now; Assumptions in normal distribution to binomial distribution

- The sample size = n = 80 > 30 . Large sample

-  np = 80 × 0.15 = 12 > 10

- nq = 80 × 0.85 = 68 > 10

so

80 × 0.15 = 12

80 × 0.20 = 16

To find P(12 < X < 16):

Z = (16 - 12) / 3.1937

= 4 / 3.1937

= 1.2525

Table of Area Under Standard Normal Curve gives area = 0.3944

Therefore the probability that between 15% and 20% of the donors on a given day have a blood type of B is 0.3944

answer: the answer is one of

step-by-step explanation:   we are given to write a proper fraction where the whole is divided into an even number of equal parts less than ten, and an odd number of those parts exist.

an even number less than 10 may be one of 2, 4, 6 or 8. so, the whole may be one of these four evens.

now, an odd number of these parts must exist, so the numerator must be an odd number, one of 1, 3, 5 or 7. it cannot be 9 because then the fraction will become improper.

thus, our fraction may be one of the following

can you add an image ?

step-by-step explanation: