Assume 44% of us have Group O blood. A hospital is conducting a blood drive beca

Question

Assume 44% of us have Group O blood. A hospital is conducting a blood drive because its supply of Group O blood is low, and it needs at least 140 donors of Group O blood. If 290 volunteers donate blood, estimate the probability that the number with Group O blood is at least 140. Is the pool of 290 volunteers likely to be sufficient?

a) P(Xgreater than or equals140) =

(Round to four decimal places as needed.)

(b) What does the result from part (a) suggest?

a..The pool is likely to be sufficient because P(x greater than or equals140)   is less than 50 %.

B. the pool is not likely to be sufficient

because P(xgreater than or equals140) is more than 50 %.

C. The pool is likely to be sufficientThe pool is likely to be sufficient

because P(x greater than or equals140) is more than 50 %.

D. The pool is not likely to be sufficient. because P(xgreater than or equals140) is less than 50 %.

Explanation / Answer

A)

We first get the z score for the critical value:          
          
x = critical value =    139.5      
u = mean = np =    127.6      
          
s = standard deviation = sqrt(np(1-p)) =    8.453165088      
          
Thus, the corresponding z score is          
          
z = (x-u)/s =    1.407756725      
          
Thus, the right tailed area is          
          
P(z >   1.407756725   ) =    0.079601559 [ANSWER]

****************************

b)

As the probability is less than 50%, then

OPTION D: D. The pool is not likely to be sufficient. because P(xgreater than or equals140) is less than 50 % [ANSWER]

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.