Conditional Probability Answers

A hat contains slips of paper with the names of the 26 other students in Eduardo’s class on them, 10 of whom are boys. To determine his partners for the group project, Eduardo has to pull two names out of the hat without replacing them.

Use the Venn diagram to calculate probabilities.

Lola pulls two marbles from a bag containing four red marbles, four blue marbles, and 12 yellow marbles without replacing them.What is the probability that she pulled out a red marble first and a yellow marble second? Express your answer in decimal form, rounded to the nearest hundredth.

In the drawing, six out of every 10 tickets are winning tickets. Of the winning tickets, one out of every three awards is a larger prize.What is the probability that a ticket that is randomly chosen will award a larger prize?

Seventy-five percent of the flowers in the arrangement are roses and the rest are tulips. Of the tulips, 50 percent are pink.To the nearest whole percent, what is the probability that a randomly chosen flower from the arrangement is a pink tulip?

Use the Venn diagram to calculate probabilities.

Nadia’s bookshelf contains 10 fiction books, two reference books, and five nonfiction books.What is the probability that she randomly picks up a reference book and then, without replacing it, picks up a nonfiction book?

Twenty-two percent of the large pieces of mail that Rachel received this week were magazines and the rest were catalogs. Of the catalogs, 36 percent were for clothing.To the nearest whole percent, what is the probability that a randomly chosen large piece of Rachel’s mail was a clothing catalog?

If events A and B are independent, what must be true?

If events A and B are independent, and the probability that event A occurs is 83%, what must be true?