Binomial Distribution & Expected Value Math AI SL

Terry purchases a small pack of Narcissus Poeticus seeds. The seed packaging claims that the germination rate is 75%.

Terry sows 5 seeds at random in his garden. Find the probability that at least one will germinate.

• 0.999

• 0.001

• 0.500

• 0.750

• .000977

Answer explanation

Alex works as a health insurance agent for Medical Benefits Fund. The probability that he succeeds in selling an insurance policy to a given customer aged 25 years or older is 0.45. On a given day he interacts with 8 customers in this age range. Find the probability that he will sell exactly 2 insurance policies on this day.

• 0.157

• 0.0632

• 0.220

• 0.780

• 0.999

Answer explanation

A bias coin has a probability of showing heads as 0.4. Marko pays $10 to play a game where he flips the coin. He gets no money if he flips a tails, and gets $k if he flips heads. The game is fair. Find the value of k.

(a)  

Answer explanation

A multiple choice exam contains 20 questions, with each question containing four possible answers. Each question has only one correct answer. Jack takes the exam and randomly guesses on every question. Find the expected number of questions Jack guesses correctly.

(a)  

Answer explanation

In a particular school in Tuscon, Arizona, the probability of a student being left handed is 0.475. In a class of 15 students, what is the probability that there are more right handed students than left handed students? (round to 3 sf)

(a)  

Answer explanation

A multiple choice exam contains 20 questions, with each question containing four possible answers. Each question has only one correct answer. Jack takes the exam and randomly guesses on every question. Find the standard deviation of this distribution. Round to 3 sig figs.

(a)