Question

In a given binomial distribution, there are 625 trials, & the probability of success is p=0.29. What is the variance?

Answer 1

ANSWER

A. 128.7


EXPLANATION


The variance of a binomial distribution is calculated using the formula,

$\sigma ^{2} = n \times p \times q$

where

$n = 625$
is the number of trials and
$p = 0.29$
is the probability of a success and

$q = 1 - 0.29 = 0.71$


is the probability of failure.


We just have to substitute the given values into the formula to obtain,



$\sigma ^{2} = 625 \times 0.29 \times 0.71$


$\sigma ^{2} =128.7$

to the nearest tenth.


The correct answer is A.