Question 369622
Find the probability that the student answers none correctly.
P(none)+P(not none)=1
P(not none)=1-P(none)
So "not none" means he answer at least one correctly... up to and including all 10 correctly
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P(none)={{{(0.5)^10=0.0009765625}}}
P(not none)={{{1-0.0009765625}}}
P(not none)={{{0.9990234}}}