Question

In a survey, 3 of 4 students said the courts show "too much concern" for criminals. Find the probability that at most 3 out of 7 randomly selected students will agree with this statement. Round your answer to the nearest thousandth.

Answer 1

p(too much) = 3/4 = 0.75
1-p = 0.25

n = 7 , c = 0, 1 , 2, 3

C(7,0) = 1 C(7,1)=7 C(7,2)=21 C(7,3)=35
p(0) = 1*.75^0*.25^7 = .25^7=.00006
P(1) = 7*.75^1*.25^6 = .00128
P(2) = 21*.75^2*.25^5= .01153
P(3) = 35*.75^3*.25^4= .05768
add them :)

Answer 2

0.07055