A survey found that 10% of Americans believe that hey have seen a UFO. For a sample of 10 people, find each probability:
a. That at least 2 people believe that they have seen a UFO
b. That 2 or 3 people believe that they have seen a UFO
c. That exactly 1 person believes that he or she has seen a UFO
+1223 a) find the probability that 0 or 1 people have believed that they have seen a UFO, then subtract from 1.
\(1 - (0.1)^{0}(0.9)^{10} - (0.1)^{1}(0.9)^{9} \approx 0.6125 = \boxed{61.25\%}\)
b) \((0.1)^2(0.9)^8 + (0.1)^3(0.9)^7 \approx 0.00478 = \boxed{0.478\%}\)
c) \((0.1)^1(0.9)^9 \approx 0.0387 = \boxed{3.87\%}\)
