A new medical test has been designed to detect the presence of the mysterious Brainlesserian disease. Among those who have the disease, the probability that the disease will be detected by the new test is 0.74. However, the probability that the test will erroneously indicate the presence of the disease in those who do not actually have it is 0.04. It is estimated that 17 % of the population who take this test have the disease. If the test administered to an individual is positive, what is the probability that the person actually has the disease? Answer:

A reader wrote in to the “Ask Marilyn” column in Parade magazine to say that his grandfather told him that in three-quarters of all baseball games, the winning team scores more runs in one inning than the losing team scores in the entire game. (This phenomenon is known as a “big bang.”) Marilyn responded that this proportion seemed too high to be believable. Let p be the proportion of all major-league baseball games in which a “big bang” occurs. To investigate this claim, we randomly selected one week of the 2006 major-league baseball season, which turned out to be July 31-August 6, 2006. Then we examined the 95games played that week to determine which had a big bang and which did not. Of the95 games in our sample, 47 contained a big bang. Use a two-sided alternative, state the null and alternative hypothesis (in symbols and in words) for testing Marilyn’s claim. 7. Determine the test statistic and p-value. 8. What conclusion would you draw concerning Marilyn’s conjecture using the…

Pregnant women are screened for a birth defect called Down syndrome. Down syndrome babies are mentally and physically challenged. Some mothers choose to abort the fetus when they are certain that their baby will be born with the syndrome. The most common screening is maternal serum screening, a blood test that looks for markers in the blood to indicate whether the birth defect may occur. The false-positive and false-negative rates vary according to the age of the mother.  Mother’s Age    False-Positive Rate    False-Negative RateUnder 30    0.040    0.37630-34    0.082    0.29035-37    0.178    0.269Over 38    0.343    0.029 The probability that a baby has Down syndrome is primarily a function of the mother’s age. The probabilities are listed here. Age    Probability of Down Syndrome25    1/130030    1/90035    1/35040    1/10045    1/2549    1/12 For each of the age 25, 30, 35, 40, 45 and 49, determine the probability of Down syndrome if the maternity serum screening produces a…

A political scientist claims that 38% of first-year college students characterize themselves as being “moderate” or “middle of the road” as far as their political affiliation is concerned.   Believing this claimed value is too high, you survey a random sample of 400 first-year college students and find that 120 characterize themselves as being “moderate” or “middle of the road.”    Based on this information, what will the test statistic be? Choose the answer below that is closest to what you calculate, and try not to do a lot of rounding until you get to the very end of your calculations.   1. -0.3 2. -1.2 3. -2.6 4. -3.3 5. None of the other answer options are correct because the test statistic should be positive, not negative.

Cody took his first physics exam and scored an 80. The population mean for this exam is 70, and the standard deviation is 5. What is the probability of selecting a person with a score greater than Cody’s?

One environmental group did a study of recycling habits in a California community. It found that 75% of the aluminum cans sold in the area were recycled. (Use the normal approximation. Round your answers to four decimal places.) (a) If 389 cans are sold today, what is the probability that 300 or more will be recycled? (b) Of the 389 cans sold, what is the probability that between 260 and 300 will be recycled   Please help- I have been working on this for two days!

A poll found that 80% of American adults believed that there was a conspiracy in the death of President Kennedy. A later poll asked 1097 American adults if they believe there was a conspiracy in the assassination, and found that 834 believe there was a conspiracy. Do the data show that the proportion of Americans who believe in this conspiracy has decreased? Test at the 1% level. State the hypotheses. Họ: P ?v H,: P ?v Calculate the test statistic. Round to four decimal places. p = Calculate the standardized test statistic. Round to three decimal places. Z = Find the p-value. Round to four decimal places. p-value = State your decision. O Since the p-value is greater than .01, fail to reject Ho. O Since the p-value is less than .01, fail to reject Ho. O Since the p-value is less than .01, reject Họ- O Since the p-value is greater than .01, reject Ho. Interpret the results. O At the 1% level of significance, there is not enough evidence to show that the proportion of American adults who…

What is a null hypothesis? a. A hypothesis that states there is an effect or relationship in the population b. A hypothesis that states there is no effect or relationship in the population c. A hypothesis that is always rejected in hypothesis testing d. A hypothesis that supports the researcher's prediction

A psychologist believes that 65% of male drivers when lost continue to drive hoping to find the location they seek rather than ask directions. To examine this belief, he took a random sample of 350 male drivers and asked each what they did when lost. Assume that the sampling distribution of the sample proportion of male drivers who continue driving is at least approximately normal. If the belief is true, determine the probability that less than 60% said they continue driving. Show your work below

Last year the average math SAT score for students at one school was 775. the Headmaster introduced new methods hoping to improve scores. this year , the math mean SAT score for a sample of students was 1178. If the teaching had no effect, there would be roughly a 3 in 100 chance of seeing such an increase. Does the result have STATISTICAL significance? does the result have PRACTICAL significance? exlain your answer