The probability of a randomly selected adult in one country being infected with a certain virus is 0.006. In tests for the​ virus, blood samples from 25 people are combined. What is the probability that the combined sample tests positive for the​ virus? Is it unlikely for such a combined sample to test​ positive? Note that the combined sample tests positive if at least one person has the virus.

Suppose a math class contains 41 students. There are 18 females (three of whom speak Spanish) and 23 males (six of whom speak Spanish). Give all answers as decimals to at least two decimal places.1. What is the probability that a randomly selected student speaks Spanish, given that the student is female?   2. What is the probability that a randomly selected student does not speak Spanish, given that the student is male?   3. What percent of Spanish speaking students are male?   4. If someone does not speak Spanish what is the probability they are female?

Samuel F.B. Morse (1791 – 1872), the creator of Morse Code, claimed that 12% of all letters used in the English language were “e”s.  Suppose random samples of 196 letters are selected from a book What is the probability that a random sample of 196 letters will contain at least 10% "e"s? Type your calculated z-score here. Express its value to the nearest hundredth (two decimal places).  Type your probability here. Express its value to four decimal places. Do not round.

3. For each experiment, fill in the blank with the letter for the probability histogram that corresponds to the quantity indicated. Experiment 1: A gambling game has a 30% chance of winning $2 and a 70% chance of losing $1. We play the game 100 times and keep track of the net amount won or lost. Experiment 2: We flip a coin 40 times and keep track of the number of heads. 0.08 90'0 0.12 0.08 0.04 000 0 0 20 10 40 20 60 8 80 30 (a) 100 (c) (e) 40 0.00 0.012 0.008 1000 0000 -100 -50 -100 -50 0 0 50 T 50 (b) 100 150 200 30 (d) (f) 100 150 200

Suppose a math class contains 37 students. There are 19 females (six of whom speak Spanish) and 18 males (five of whom speak Spanish). Give all answers as decimals to at least two decimal places.1. What is the probability that a randomly selected student speaks Spanish, given that the student is female?   2. What is the probability that a randomly selected student does not speak Spanish, given that the student is male?   3. What percent of Spanish speaking students are male?   4. If someone does not speak Spanish what is the probability they are female?

34% of a certain breed of rabbits are born with long hair. What is the probability that in a litter of 11 rabbits, exactly 6 will have long hair? (Give your answer correct to three decimal places.)

It is estimated that one in twenty-five Americans is a cystic fibrosis carrier. Find the probability that a randomly selected American couple's child will have cystic fibrosis (assuming that they are unrelated). (Enter your answer to four decimal places.)