LAST KHAN EVER 2024 GUIDE WITH ACTUAL QUESTIONS AND ANSWERS VERIFIED 100%;(GUARANTEED SUCCESS)

LAST KHAN EVER 2024 GUIDE WITH ACTUAL QUESTIONS AND ANSWERS VERIFIED 100%;(GUARANTEED SUCCESS) A city had an unemployment rate of 7%7%7, percent. The mayor pledged to lower this figure and supported programs to decrease unemployment Ans - H0:p=7% Ha:p<7% A newspaper report claims that 30%30%30, percent of all tea-drinkers prefer green tea to black tea. Leo is the office manager at a company with thousands of employees. Ans - ...equal to 30%30%30, percent. A quality control engineer is testing the battery life of a new smartphone. The company is advertising that the battery lasts 242424 hours on a full-charge, but the engineer suspects that the battery life is actually less than that. They take a random sample of 505050 of these phones to see if their average battery life is significantly less than 2424 Ans - H0:μ=24 hours Ha:μ<24 hours type ii error-b A healthcare provider saw that 48%48%48, percent of their members received their flu shot in a recent year. The healthcare provider tried a new advertising strategy in the following year, and they took a sample of members to test if the proportion who received their flu shot had changed. Ans - H0:p=48% Ha:p=48% Lena is a college basketball player who has made 75%75%75, percent of the free-throws she has attempted in her career. She decided to practice a new technique for shooting her free-throws. Ans - ...not equal to 75%75% A restaurant owner installed a new automated drink machine. The machine is designed to dispense 530 mL530 mL530, start text, space, m, L, end text of liquid on the medium size setting. Ans - H0:μ=530 mL Ha:μ>530 mL A fair coin should land showing tails with a relative frequency of 50%50%50, percent in a long series of flip Ans - H0:p=50% Ha:p>50% Reports say that the mean birth weight of babies of European heritage is 3.5 kg3.5 kg3, point, 5, start text, space, k, g, end text. Marta wants to perform a significance test to see if this holds true in her nation. Ans - ...equal to 3.5 kg3.5 kg3, point, 5, start text, space, k, g, end text. A fast-food company advertises that the pre-cooked weight for its burgers is, on average, 0.2 kg0.2 kg0, point, 2, start text, space, k, g, end text. The company runs a regular quality control test that involves weighing a sample of burgers to see if the burgers are too light or too heavy. If the sample mean weight is significantly different than 0.2 kg0.2 kg0, point, 2, start text, space, k, g, end text, then they recycle the entire batch. Ans - H0Ha:μ=0.2 kg:μ=0.2 kg d A ketchup company regularly receives large shipments of tomatoes. For each shipment that is received, a supervisor takes a random sample of tomatoes to see what percent of the sample is bruised and performs a significance test. If the sample shows convincing evidence that more than 10%10%10, percent of the entire shipment of tomatoes is bruised, then they will request a new shipment of tomatoes. Ans - H0:p=0.1 Ha:p>0.1 The National Sleep Foundation recommends that teenagers aged 141414 to 171717 years old get at least 888 hours of sleep per night for proper health and wellness. Ans - ...less than 8 hours. A local pizza store knows the mean amount of time it takes them to deliver an order is 454545 minutes after the order is placed. The manager has a new system for processing delivery orders, and they want to test if it changes the mean delivery time. They take a sample of delivery orders and find their mean delivery time is 484848 minutes. Ans - a A nutritionist suspected that her company's clients had below average cholesterol. They obtained a random sample of 888 clients of the same age and gender. These clients had a mean cholesterol level of xˉ=4.28 mmol/Lxˉ=4.28 mmol/Lx, with, bar, on top, equals, 4, point, 28, start text, space, m, m, o, l, slash, L, end text (millimoles per liter). Ans - B .05 An economist read a report that claimed that 60%60%60, percent of residents in her large city owned their homes. She wondered if that figure was still accurate, so she took a random sample of n=50n=50n, equals, 50 residents in the city and observed that p^=70%p^=70%p, with, hat, on top, equals, 70, percent of those sampled owned their homes. Ans - D A class in New Zealand found a report suggesting that teenagers' heights in New Zealand are approximately normally distributed with a mean of 160 cm160 cm160, start text, space, c, m, end text and a standard deviation of 15 cm15 cm15, start text, space, c, m, end text. They thought the mean height at their school was probably larger, so they took a random sample of n=24n=24n, equals, 24students. The mean height of students in their sample was xˉ=166.5 cmxˉ=166.5 cmx, with, bar, on top, equals, 166, point, 5, start text, space, c, m, end text. Ans - C Mr. Jensen told his class that he plays basketball frequently, and he claimed that he could make 80%80%80, percent of his free-throw attempts. The class suspected that Mr. Jensen was actually less than an 80%80%80, percent free-throw shooter. To test their theory, they had Mr. Jensen shoot a series of 404040 free-throws. He made p^=60%p^=60%p, with, hat, on top, equals, 60, percent of them. Ans - A A large school district knows that 75%75%75, percent of students in previous years rode the bus to school. Administrators wondered if that figure was still accurate, so they took a random sample of n=80n=80n, equals, 80 students and found that p^=65%p^=65%p, with, hat, on top, equals, 65, percent of those sampled rode the bus to school. Ans - B t is commonly said that 10%10%10, percent of people are left-handed, but Lilianna suspected that a higher proportion of art students at her university are left-handed. To test this theory, she took a sample of art students and found that p^=14%p^=14%p, with, hat, on top, equals, 14, percent of the sample was left-handed. Ans - C The ages of workers in a certain industry are approximately normally distributed with a mean of 303030 years and a standard deviation of 3.53.53, point, 5 years. A recruiter wondered if that held true for workers in a certain state. The recruiter took a random sample of n=3n=3n, equals, 3 of these workers from the state, and the mean age of the workers in the sample was xˉ=26xˉ=26x, with, bar, on top, equals, 26 years. Ans - c p-value≈0.07 Evie read an article that said 6%6%6, percent of teenagers were vegetarians, but she thinks it's higher for students at her large school. To test her theory, Evie took a random sample of 252525 students at her school, and 20%20%20, percent of them were vegetarians. Ans - D A class found a report suggesting that teenagers' foot lengths are approximately normally distributed with a mean of 23 cm23 cm23, start text, space, c, m, end text and a standard deviation of 2.6 cm2.6 cm2, point, 6, start text, space, c, m, end text. They wondered if this held true at their school, so they took a random sample of n=9n=9n, equals, 9 students. The mean foot length of students in their sample was xˉ=24.6ˉ cmxˉ=24.6ˉ cmx, with, bar, on top, equals, 24, point, 6, with, bar, on top, start text, space, c, m, end text. Ans - D .08 A factory produces ball bearings whose diameters are meant to have a mean of 3 mm3 mm3, start text, space, m, m, end text. Suppose that the actual sizes are normally distributed with a mean of 3 mm3 mm3, start text, space, m, m, end text and a standard deviation of 0.2 mm0.2 mm0, point, 2, start text, space, m, m, end text. The overseers took a random sample of n=100n=100n, equals, 100 ball bearings to see if their mean diameter was significantly different than the target. The mean diameter of the ball bearings in the sample was xˉ=2.96 mmxˉ=2.96 mmx, with, bar, on top, equals, 2, point, 96, start text, space, m, m, end text. Ans - D Elian heard that spinning a coin on a flat surface—rather than flipping it—made the probability of the coin landing showing "heads" something other than 50%50%50, percent. To test this theory, he spun a nickel a series of 808080 times and observed that p^=60%p^=60%p, with, hat, on top, equals, 60, percent of the spins landed showing "heads." Ans - C It is commonly said that 10%10%10, percent of people are left-handed, but Lilianna suspected that a higher proportion of art students at her university are left-handed. To test this theory, she took a sample of art students and found that p^=14%p^=14%p, with, hat, on top, equals, 14, percent of the sample was left-handed. Ans - C An employee at an aquarium monitors how much their sea otters eat. The amount of food a particular otter eats daily is approximately normally distributed with a mean of 171717 pounds and a standard deviation of 111 pound. They suspected this otter was not eating enough, so they took a random sample n=10n=10n, equals, 10 days and observed a sample mean of xˉ=16.5xˉ=16.5x, with, bar, on top, equals, 16, point, 5 pounds of food per day. Ans - D Ricky is testing soil for a contaminant at a building site. He'll take action to stop construction if there's strong evidence that the soil has more than parts per million (ppm) of the contaminant. He plans on using soil from n=30n=30n, equals, 30 randomly selected locations at the building site. His hypotheses are H0:μ≤400 ppmH0:μ≤400 ppmH, start subscript, 0, end subscript, colon, mu, is less than or equal to, 400, start text, space, p, p, m, end text and Ha:μ>400 ppmHa:μ>400 ppmH, start subscript, start text, a, end text, end subscript, colon, mu, is greater than, 400, start text, space, p, p, m, end text, where μμmu is the mean amount of the contaminant in the soil at this site. Ans - d type ii-bnat According to a report from the United States Environmental Protection Agency, burning one gallon of gasoline typically emits about 8.9 kg8.9 kg8, point, 9, start text, space, k, g, end text of CO2CO2start text, C, O, end text, start subscript, 2, end subscript. A fuel company wants to test a new type of gasoline designed to have lower CO2CO2start text, C, O, end text, start subscript, 2, end subscript emissions. Here are their hypotheses: Ans - b A city had an unemployment rate of 7%7%7, percent. The mayor pledged to lower this figure and supported programs to decrease unemployment. A group of citizens wanted to test if the unemployment rate had actually decreased, so they obtained a random sample of citizens to see what proportion of the sample was unemployed. Ans - d A city planner will consider adding electric vehicle charging stations if she is convinced that more than 15%15%15, percent of residents would use them. She will survey a sample of residents to test the hypotheses H0:p≤15%H0:p≤15%H, start subscript, 0, end subscript, colon, p, is less than or equal to, 15, percent vs. Ha:p>15%Ha:p>15%H, start subscript, start text, a, end text, end subscript, colon, p, is greater than, 15, percent, where ppp is the true proportion of residents that would use the stations. Ans - A A class did an experiment to see if students could taste water and identify bottled water versus tap water. Each student was presented with three cups of water—one of which contained bottled water—and they were directed to identify which cup they thought contained bottled water. The class wants to test if they correctly identified the bottled water significantly better than they would have done by simply guessing. Ans - a A manufacturer knows that 2%2%2, percent of its microchips are produced with a certain defect. They decide to change their process to make it more efficient, and they want to test if the new process has the same defect rate or not. Ans - c A business knows that 3%3%3, percent of its orders that are shipped to customers arrive late. The business changes its system for processing orders, and they want to test if the proportion of orders that arrive late has changed. They take a sample of orders and find that 202020—or 4%4%4, percent of orders sampled—arrived late. Let Ans - a A campaign manager for a political candidate released a series of advertisements criticizing their opponent in an upcoming election. Their opponent previously had the support of 45%45%45, percent of voters, and the campaign manager wants to sample voters to test if support for their opponent has decreased. Ans - c A business knows that 30%30%30, percent of its customers are less than 252525 years old. The business wants to increase this percentage, so they create a marketing campaign that targets this age group. They plan on taking a sample of customers after the marketing campaign is complete to test if the proportion of customers in that age group has significantly increased. Ans - D No, because 0.177>0.100.177>0.100, point, 177, is greater than, 0, point, 10. read a report saying that 49%49%49, percent of teachers in the United States were members of a labor union. She wants to test whether this holds true for teachers in her state, so she is going to take a random sample of these teachers and see what percent of them are members of a union. Ans - a A large poll showed that 42%42%42, percent of adults approved of their nation's prime minister. Margot wants to test if it is now lower, so she takes a random sample of 1,0001,0001, comma, 000 adults in that nation and finds that —or 39%39%39, percent of those sampled—approved of the prime minister. Ans - d The mayor of a town sees an article that claims the national unemployment rate is 8%8%8, percent. They suspect that the unemployment rate is lower in their town, so they plan to take a sample of residents to test if the proportion of residents that are unemployed in the sample is significantly lower than the national rate. Ans - c Fay read an article that said 26%26%26, percent of Americans can speak more than one language. She wants to test if this figure is higher in the city she lives, so she plans on taking a sample of people to see what proportion of them speak more than one language. Ans - d Elliot read a report from a previous year saying that 6%6%6, percent of adults in his city biked to work. He wants to test whether this has changed, so he is going to take a random sample of adults in his city and see what percent of them bike to work. Ans - b According to a very large poll in 2015, about 90%90%90, percent of homes in California had access to the internet. Market researchers want to test if that proportion is now higher, so they take a random sample of 1,0001,0001, comma, 000 homes in California and find that —or 92%92%92, percent of homes sampled—have access to the internet. Ans - d A campaign manager for a political candidate released a series of advertisements criticizing their opponent in an upcoming election. Their opponent previously had the support of 45%45%45, percent of voters, and the campaign manager wants to sample voters to test if support for their opponent has decreased. Ans - c Lian read a report claiming that 9%9%9, percent of people in her country were classified as living in poverty. She wonders if this holds true in her large city, so she obtains an SRS of 505050 people from her city. She wants to use the sample data to test H0:p=0.09H0:p=0.09H, start subscript, 0, end subscript, colon, p, equals, 0, point, 09 versus Ha:p≠0.09Ha:p=0.09H, start subscript, start text, a, end text, end subscript, colon, p, does not equal, 0, point, 09, where ppp is the proportion of all people in her city that are classified as living in poverty. Ans - a,c ................................................................................................................................