Correct me please! Can you also give explanation to each problem?
Exam 1 W. Li problem 4: .4 Assume you have a small bag of M&Ms in three varieties: 40 of milk chocolate, 35 of peanut, and 25 .35 . 25 of pretzel. Suppose you don't like the pretzel flavor, so every time you pick a pretzel M&M, you put it back into the bag. If you pick any of other kinds, milk chocolate or peanut M&M, you eat it right away. Assume you pick only one M&M at a time, and you will select three times (without looking). Find the probability (in decimals) that: (15 points total) 16198 a) You will eat exactly one M&M. (5 points) Second dau First as/ICC as /98 (25 ) (85 ( 8) . 048 24/5 25/g9 draw ?S/ ico b) You will eat at least 2 M&Ms. (5 points) IS( Second 10C 45 : . $768 clicw Third drav c) You won't eat any of the M&M. (5 points) = . 016 Problem 5: Susan has been keeping statistics on lost pets in her neighborhood. She has determined that 80% of the "lost" pets turn up within a couple of weeks. She is tired of helping her friends look for pets for free, so she decides to offer her neighbors a lost pet insurance plan. If they pay her $5 to join her plan, she will look for the pet that go missing. If she cannot find the pet within a certain period (e.g., a week), she will pay the owner $50. Can she make money based on her plan? (10 points total) a) Give the probability distribution for Susan's plan in tabular form. (2 points) X 5 -50 P(x ) 8 . 2 b) Find the expected value and the standard deviation for Susan's plan. (5 points) u: 5 (. 8) 1 (- So ) (. 2) =-16 829 6 t9 + 3. = [(? ) (9 - 0 -1 * [ (8 )2 ( 9-9 ) = 20 V 6as : 25 . 06 c) How much should Susan charge if she would like to make $10 per client on average? (3 points) X 6 p(x ) S . ? $10 : .89 - 50(.8) V1 she should charge $es if she would like to make sto per clientExam 1 W. Li problem 6 : 400 college students were randomly selected for a survey . 25% take the bus to school , 10% walk , and 65% drive themselves to school . 80% of the students who drive to school are male , 70% of those who points total ) walk are female , and 65% of those who take the bus are male . A student is selected at random . ( 15 a ) Fill out a two - way contingency table . ( 6 points ) Bus walk Drive Total Male 65 12 208 285 Female 35 28 115 Total 100 40 260 400 b ) What is the probability that the chosen student is a female student and does not drives to school ? ( 3 points ) Keep your answer in FRACTION format ( DO NOT Simplify ) !* 35 + 28) 6 3 400 400 C ) What is the probability that the chosen student walks to school or this is a male student ? ( 4 points ) Keep* your answer in FRACTION format ( DO NOT Simplify ) !* 40 285 400 3 25 400 7400 : 2 d ) Are the 400 students a population or a sample ? Circle your answer . ( 2 points ) Sample Population Problem 7 : Circle the correct answer for each question . ( 1 point each - 5 points total ) 1 . Which of the following graphical method is not suitable for describing a single quantitative variable ?* A ) Dot Plot B ) Histogram\\ C ) Stem- and - Leaf Display ( Djpie Chart E ) None of the above 2 . A dataset has the median of 20 and the mean of 19.5 , then the distribution of this dataset is A ) Perfectly symmetrical B ) Bimodal ( C ) Skewed to the left D ) Skewed to the right*E ) None of the above* 3 . A fair dice is rolled 10 times . What is the standard deviation of the even number ( 2 , 4 , or 6 ) outcomes ? A ) 10 B ) 5 C ) 2.5 D / 1 . 581\\ ( E ) None of the above 4 .. Nationality would be what kind of variable ?* A ) Quantitative , Ratio B ) Quantitative , Interval C ) Qualitative , ordinal\\ . 2 5 . TWO mutually exclusive events are ( D ) Qualitative , nominal dependent . A ) Never B ) Always C ) Not Sure* D ) Sometimes E ) None of the above Problem 8 : Staple your cheat sheets to the back of the exam ( DO NOT include the binomial table ) . ( 5 points ) VI F 5
