Khan Academy | Statistics and probability | Quiz 1

Gustavo is the league's home run leader. The probabilities for his total number of home runs for the season are as follows: P (0-19 home runs) = 1/4 P (20-39 home runs) = 45% P (40+ home runs) = 0.3 Put the following events in order from least to most likely.

0-19 home runs 40+ home runs 20-39 home runs

Dalia owns a gravel pit. She took a random sample of rocks and counted 58 sedimentary rocks, 213 metamorphic rocks, and 522 igneous rocks. Use the observed frequencies to create a probability model for Dalia randomly selecting one rock from her gravel pit. Input your answers as fractions or as decimals rounded to the nearest hundredth.

0.07 0.27 0.66

Michael, Ronald, Lidia, Alexandra, and Catherine are sharing a basket of fries. The following table shows an incomplete probability model for who will eat the next fry. Person Probability Micheal 0.3 Ronald ? Lidia 0.1 Alexandra 0.32 Catherine 0.1 What is the probability that Ronald will eat the next fry?

0.18

Mahnoor randomly selects times to walk into a local restaurant and observe the type of music being played. She found that the restaurant was playing country 11 times, rock & roll 17 times, and blues 8 times. Use the observed frequencies to create a probability model for the type of music the restaurant is playing the next time Mahnoor walks in. Input your answers as fractions or as decimals rounded to the nearest hundredth.

0.31 0.47 0.22

Manny, Rachelle, and Peg race each other in carts. There are no other racers, and exactly one racer wins each race (no ties allowed!). The following graph shows an incomplete probability model for who will win any given race. What is the probability that Rachelle will win any given race?

0.4

The following table shows the length (in days) of each of the 9 Tucker family vacations. Based on this data, what is a reasonable estimate of the probability that the next Tucker family vacation last less than 3 days? Choose the best answer: Choose 1 answer:

0.56

Greg has an MP3 player called the Jumble. The Jumble randomly selects a song for the user to listen to. Greg's Jumble has 6 classical songs, 7 rock songs, and 9 rap songs on it. What is P (not a rap song)? If necessary, round your answer to 2 decimal places.

0.59

You roll a fair 6-sided die. What is P (roll an even number)? If necessary, round your answer to 2 decimal places.

1/2

Omar ordered his sister a birthday card from a company that randomly selects a card from their inventory. The company has 21 total cards in inventory. 14 of those cards are birthday cards. What is P (not a birthday card)? If necessary, round you answer to 2 decimal places.

1/3

You roll a fair 6-sided die. What is P (not a 2)? If necessary, round your answer to 2 decimal places.

1/6

The Pines Golf Course is offering free ice cream cones to golfers who hit their tee shot on the green at hole 7! The following bar graph summarizes the tee shots from this morning. Based on this data, what is a reasonable estimate of the probability that the next tee shot ends up on the green? Choose the best answer. Choose 1 answer:

17%

March Madness Movies served 23 lemonades out of a total of 111 fountain drinks last weekend. Based on this data, what is a reasonable estimate of the probability that the next fountain drink ordered is a lemonade? Choose the best answer. Choose 1 answer:

23/111

The table shows the number of feathers Patsy the Peacock sold at each of the 8 festivals this year. Based on this data, what is a reasonable estimate of the probability that Patsy sells fewer than 5 feathers next festival? Choose the best answer. Choose 1 answer:

75%

The following histogram summarizes the number of points Nate has scored each game this season. Based on this data, what is a reasonable estimate of the probability that Nate scores 88-111 points next basketball game? Choose the best answer. Choose 1 answer:

8/25

Chen has an MP3 player called the Jumble. The Jumble randomly selects a song for the user to listen to. Chen's Jumble has 4 classical songs, 3 rock songs, and 2 rap songs on it. Chen is going to listen to 360 songs. What is the best prediction for the number of times Chen will listen to a classical song? Choose 1 answer:

Close to 160 times but probably not exactly 160 times

Leo is going to use a random number generator 400 times. Each time he uses it, he will get a 1, 2, 3,4, or 5. What is the best prediction for the number of times that Leo will get an odd number?

Close to 240 times but probably not exactly 240 times.

Elizabeth is going to flip a fair coin 100 times. What is the best prediction for the number of times that the coin will land tails up? Choose 1 answer:

Close to 50 times but probably not exactly 50 times.

Mekala has an MP3 player called the Jumble. The Jumble randomly selects a song for the user to listen to. Mekala's Jumble has 4 techno songs, 2 country songs, and 3 jazz songs on it. Mekala plans to listen to 270 songs. Complete the following statement with the best prediction. Mekala will listen to... Choose 1 answer:

Close to 60 country songs but probably not exactly 60 country songs

Both Felipe and Enzo forgot to study for their science test. The probability of Felipe passing the test is 0.19. The probability of Enzo passing the test is 1/4. Which of these events is more likely, Choose 1 answer:

Enzo passes the test.

Juanita and Nina are bowling together. The probability of Juanita getting a strike next game is 24%. The probability of Nina getting a strike next game is 0.17. Which of these events is more likely? Choose 1 answer:

Juanita gets a strike next game.

Rory, Phil, and Rickie are competing in a golf match. Their probabilities of winning the match are as follows: P (Rory wins) = 20% P (Phil wins) = 0.05 P (Rickie wins) = 3/4 Put the following events in order from least to most likely.

Phil wins, Rory wins, Rickie wins

Simone is stranded on an island. The probability of her finding safety by waiting for help is 1/4. The probability of her finding safety by leaving in her raft is 0.32. Which of these events is more likely? Choose 1 answer:

Simone finds safety by leaving in her raft,

The Hendricksons are in charge of bringing treats for 50 football players. They brought 3 coolers of popsicles and 2 coolers of ice cream sandwiches. Each player is going to randomly select a cooler from which to get their treat. Which statement best predicts how many football players will get a popsicle? Choose 1 answer :

There will be close to 30 football players but probably not exactly 30 football players who get a popsicle.