The three coins could land any these 8 ways:
HHH, HHT, HTH, HTT, THH, THT, TTH, TTT
P(3 heads) = 1 way out of 8 or 1/8
P(2 heads) = 3 ways out of 8 or 3/8
P(1 head) = 3 ways out of 8 or 3/8
P(0 heads) = 1 way out of 8 or 1/8
x=Winnings P(x) E(x)=x�P(x)
$3 1/8 $.375
$2 3/8 $.75
$1 3/8 $.375
-$10 1/8 -$1.25
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Total expectation = $ .25
