Binomial distribution: p = .05 , n= 50| P(4) = (50C4)(.05^4)(.95^46) Trust Your calculator is doing the computations for You: Using TI or similarly an inexpensive calculator like an Casio fx-115 ES plus P(x) is binompdf(n, p, x-value). P(4) = binompdf(50, .05, 4)= .136 P(x<2) = P(0) + P(1) Trust Your Calculator: P(x<2) = P(x ≤ 1) = binomcdf(n, p, largest x-value) =binomcdf (50,.05,1) = .2794 P(2 ≤ x ≤ 7) = P(2) + P(3) + P(4) + P(5) + P(6) + P(7) Trust Your Calculator: P(2 ≤ x ≤ 7) = P(x≤7) - P(x≤1) = .9968 - .2794 = .7174 Feeling comfortable with Your calculator is key to Your success working with the various Distributions. Wish You the Best in your Studies.