Question

Sociologists say that 80% 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 eleven married women are having coffee together one morning. Find the following probabilities. (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 nine of them dislike their mother-in-law.


(d) No more than eight of them dislike their mother-in-law.

Answer 1

Please don't hesitate to give a "thumbs up" in case you're satisfied with the answer

p(claim that their husband's mother is the biggest bone of contention in their marriages (sex and money are lower-rated areas of contention) = .80. Let this probability be "p"

We use the binomial theorm pdf to solve the problem.

a. P(all of them dislike their MIL) = ¹¹C₁₁ *.8¹¹ * .2⁰ = 0.086

b. P( none of them dislike their MIL) = ¹¹C₀* .8⁰ *.2¹¹ = 2.048*10^-8

c. P( at least 9 of them dislike their MIL) =

= ¹¹C₉* .8⁹ *.2² + ¹¹C10* .8¹⁰ *.2¹+ ¹¹C₁₁ .8¹¹ *.2⁰ = 0.617

d. P(no more than 8 of them dislike their MIL)

= 1 - P( at least 9 of them dislike their MIL)

= 1-.617

= 0.383