Question

g According to government data, 25% of employed women have never been married. If 10 employed women are selected at random, what is the probability that two or fewer of them have never been married

Answer 1

The probability is 0.5263

Explanation:

Probability of employed women being unmarried = 25% = 0.25 ( let this be p)

Probability of employed women ever being married = 1-0.25 = 0.75 (let this be q)

Now, we want to calculate the probability that two or less have never been married

We can use the Bernoulli approximation of the Binomial distribution here;

In this case, we have three cases

We have cases of;

Exactly two + Exactly one + None

For exactly two;

10 C 2 0.25^2 0.75^8 = 0.282

For exactly one

10 C 1 0.25^1 0.75^9 = 0.188

For none

10C 0 0.25^0 0.75^10 = 0.0563

Adding these 3 to get the probability of two or fewer, we have;

0.0563 + 0.188 + 0.282 = 0.5263