Question 855229
according to a may 2013 gallup poll, 53% of americans support the legalization of same sex marriage. 
b. if a random sample of 10 americans is found, how many people would we expect to support the legalization of same sex marriage
E(x) = np = 10*0.53 = 5.3
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c. what would the standard deviation of this 10 person distribution be
std = sqrt(npq) = sqrt(5.3*0.47) = 1.58
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d. if we would randomly sample 10 people, what is the probability that exactly 6 would support the legalization of same sex marriage.
P(x = 6) = 10C6(0.53)^6(0.47)^4 = binompdf(10,0.53,6) = 0.2271
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e if we would randomly sample 10 people, what is the probability less than 6 would support the legalization of same sex marriage. 
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P(0<= x <=5) = binomcdf(10,0.53,5) = 0.5474
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f. if we secure a simple randome sample of 250 americans, what is the probability that less than 120 would support the legalization of same sex marriage

P(x < 120) = binomcdf(250,0.53,119) = 0.0499
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Cheers,
Stan H.
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