Question

Using the Binomial Probability table, find P(X) when n = 7, X < 3, and p = 0.5 A. 0.273 B. 0.500 C. 0.227 D. 0.773

Answer 1

0.227

Explanation:

Given that X is binomial with n=7 and p =0.5

To find the probability for P(X<3)

i.e. we have to find prob as =P(x=0,1,2)

=P(X=0)+P(X=1)+P(x=2)

P(X=r)=7Cr(0.5)^7

Using binomial table we find prob

P(X<3)=0.2265

Round off this to 3 decimals as

0.227

Hence answer is 0.227