Question

Nine percent of men and 0.25% of women cannot distinguish between the colors red and green. This is the type of color blindness that causes problems with traffic signals.

(a)	If 11 men are randomly selected for a study of traffic signal perceptions, find the probability that at least 3 of them have this type of color blindness.

(b)	In a group of 160 men, find the mean number that are color blind.

(c)	In a group of 160 men, find the standard deviation of the number that are color blind.

(d)

Suppose that a group of 160 men are randomly selected, and 19 of them are color blind. Is this a significantly high number that would perhaps suggest that the given percentage of men that are color blind (i.e., 9%) is not correct?   (A) Yes, because 19 is a lot. (B) No, because 19 is less than 25. (C) Yes, because 19 out of 160 is 11.88%, which is a higher percentage than expected (D) No, because 19 out of 160 is 11.88%, which is not much higher than expected. (E) No, because 19 is less than 21.64. (F) No, because 19 is not a lot. (G) Yes, because 19 is greater than 18.

Answer 1