Maharashtra State BoardHSC Arts 12th Board Exam
Advertisement Remove all ads

Let X ~ B(n, p) if E(X) = 5 and Var(X) = 2.5, find n and p. - Mathematics and Statistics

Advertisement Remove all ads
Advertisement Remove all ads
Advertisement Remove all ads
Sum

Let X ~ B(n, p) if E(X) = 5 and Var(X) = 2.5, find n and p.

Advertisement Remove all ads

Solution

X ~ B(n, p)

Given: E(X) = 5 and Var(X) = 2.5

np = 5  and npq = 2.5

∴ `"npq"/"np" = 2.5/5`

∴ q = 0.5 = `5/10 = 1/5`

∴ p = 1 - p = `1 - 1/2 = 1/2`

Substituting p = `1/2` in np = 5, we get

`"n"(1/2) = 5`

∴ n = 10

Hence, n = 10 and p = `1/2`

Concept: Variance of Binomial Distribution (P.M.F.)
  Is there an error in this question or solution?

APPEARS IN

Balbharati Mathematics and Statistics 2 (Arts and Science) 12th Standard HSC Maharashtra State Board
Chapter 8 Binomial Distribution
Miscellaneous exercise 8 | Q 2.2 | Page 253
Advertisement Remove all ads
Share
Notifications

View all notifications


      Forgot password?
View in app×