A magician has 20 coins in his pocket. Twelve of these coins are normal fair coins (with one head and one tail) and eight are defective coins with heads on both sides. The magician randomly draws a coin from his pocket and flips it. Given that the flipped coin shows a head, what is the probability that it is defective?

Select the correct answer from each drop-down menu. james needs to clock a minimum of 9 hours per day at work. the data set records his daily work hours, which vary between 9 hours and 12 hours, for a certain number of days. {9, 9.5, 10, 10.5, 10.5, 11, 11, 11.5, 11.5, 11.5, 12, 12}. the median number of hours james worked is . the skew of the distribution is

Arandomized controlled trial is designed to evaluate the effect of metoprolol in patients with heart failure. while preparing for statistical analysis, the researcher reviews some common types of statistical errors. which of the following statements is true regarding a type i error in a clinical study? a. the study is not significantly powered to detect a true difference between study groups. bthe null hypothesis is true but is rejected in error. c. the null hypothesis is false but is accepted in error. d. type i error is also known as beta and is usually 0.1 or 0.2. e. type i error depends on the study's confidence interval.

If 5x - 2 = -12, then x = a) -50 b) -4.4 c) -2.8 d) -2