Two coins are randomly selected from a pocket containing two quarters, one dime, and one nickel. A random variable is defined as the total value of the two coins selected. Find the expected value (in cents).
Q1 = first quarter
Q2 = second quarter
D = dime
N = nickel
Selection x=Value p=Probability x·p
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Q1,Q2 50¢ ¢ = ¢
Q1,D 35¢ ¢ = ¢
Q1,N 30¢ ¢ = ¢
Q2,D 35¢ ¢ = ¢
Q2,N 30¢ ¢ = ¢
D,N 15¢ ¢ = ¢
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E(x) = ∑x·p = ¢ = ¢ = ¢
Edwin