If 28% of students in college are near-sighted, the probability that in a randomly chosen group of 20 college students, exactly 4 are near-sighted is closest to
(a) 17%
(b) 18%
(c) 12%
(d) 16%

(D) 16%

Step-by-step explanation:

Binomial probability formula :-

, where n is the sample size , p is population proportion and P(x) is the probability of getting success in x trial.

Given : The proportion of students in College are near-sighted : p= 0.28

Sample size : n= 20

Then, the the probability that in a randomly chosen group of 20 College students, exactly 4 are near-sighted is given by :_

Hence, the probability that in a randomly chosen group of 20 College students, exactly 4 are near-sighted is closest to 16%.

C. 6x^2 + 2x - 5

Step-by-step explanation:

4x^2 + 2x^2 = 6x^2

-5x + 7x = 2x

3 - 8 = -5

Therefore,

4x^2-5x+3 + 2x^2+7x-8 = 6x^2+2x-5