2p+2q=21p+qE(x2)=i=0∑3xi2p(xi)=0⋅p+1⋅p+4⋅q+9q=p+13qE(x)=i=0∑3xi2p(xi)=0⋅p+1⋅p+2q+3q=p+5qp+13q=2(p+5q)p=3q So, q=81&p=83 So, 8p−1=2 Option (2)
Let a random variable X take values 0,1,2,3 with P(X=0)=P(X=1)=p,P(X=2)=P(X=3) and E(X2)=2E(X). Then the value of 8p−1 is :
Held on 7 Apr 2025 · Verified 6 Jul 2026.
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