If p.m.f. of a d.r.v. X is P(= \(\frac{c}{x^{3}}\), for x = 1, 2, 3 and = 0, otherwise (elsewhere), then E(=
A. \(\frac{343}{297}\)
B. \(\frac{294}{251}\)
C. \(\frac{297}{294}\)
D. \(\frac{294}{297}\)
Answer:B
If p.m.f. of a d.r.v. X is P(= \(\frac{c}{x^{3}}\), for x = 1, 2, 3 and = 0, otherwise (elsewhere), then E(=
A. \(\frac{343}{297}\) B. \(\frac{294}{251}\) C. \(\frac{297}{294}\) D. \(\frac{294}{297}\)