np=2
npq=1
∴q=21
p=1−q=21
n=4
P(X≥1)=1−4C0(21)4(21)0
1−161=1615
JEE Main 2015 — Mathematics Probability & Statistics
If the mean and the variance of a binomial variate X are 2&1 respectively, then the probability that X takes a value greater than or equal to one is:
Held on 11 Apr 2015 · Verified 6 Jul 2026.
161
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1615
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