Question

Sociologists say that 90% of married women claim that their husband's mother is the biggest bone of contention in their marriages (sex and money are lower-rated areas of contention). Suppose that eight married women are having coffee together one morning. Find the following probabilities. (For each answer, enter a number. Round your answers to three decimal places.)

(a)

All of them dislike their mother-in-law.

(b)

None of them dislike their mother-in-law.

(c)

At least six of them dislike their mother-in-law.

(d)

No more than five of them dislike their mother-in-law.

Answer 1

We can solve this by using Binomial distribution

X ~ Binomial (n, p)

X: Random variable for the number of women disliking their mother in law

X~ Binomial(8, 0.9)

a)

All of them dislike their mother-in-law. So, x = 8

b)

None of them dislike their mother-in-law. So x = 0

c)

At least six of them dislike their mother-in-law. So, x > =6.

P(X >=6) = P(x = 6) + P(x =7) + P(x=8) = 0.96190821

d)

No more than five of them dislike their mother-in-law. So, x < =5

P(x < =5) = 0.03809179