Question 177892
let a = probability they play in the next superbowl.
let b = probability they do not play in the next superbowl.
p(a) + p(b) = 1
p(a) = 9*p(b)
this means that:
9*p(b) + p(b) = 1
which means:
10*p(b) = 1
divided both sides of this equation by 10, and you get:
p(b) = 1/10 = .1
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since p(a) = 9 * p(b), this means that:
p(a) = .9
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