Find the probability

Question

A school newspaper reporter decides to randomly survey 17 students to see if they will attend Tet festivities this year. Based on past years, she knows that 12% of students attend Tet festivities. We are interested in the number of students who will attend the festivities.

Find the probability that more than 2 students will attend. (Round your answer to four decimal places.)

Answer 1

mean = np = .12x17 =2.04

variance =npq = 2.04(.88) =1.7952

standard deviation =sqrnpq = sqr1.7952 =1.33985

z score = (x-np)/sqrnpq = (2-2.04)/1.33985=.02985

use z tables or a calculator to find Pr(x>2)= slightly greater than Pr(x>0)=.5 =50%

Pr(x>2) = .5119 = 51.19%