A researcher is studying the relationship between the number of hours studied (X) and exam scores (Y). The regression equation is given as Y = 50 + 5X. Calculate the predicted exam score if a student studies for 4 hours.

A factory produces light bulbs, and 95% of the bulbs pass the quality control test. If a random sample of 20 bulbs is taken, what is the probability that exactly 18 bulbs will pass the test?

The average height of adult men in a certain country is 175 cm with a standard deviation of 8 cm. If a random sample of 50 men is taken, what is the probability that their average height will be between 173 cm and 177 cm?

actor es this question below Consider an experiment to determine the effects of alcohol and marijuana on driving. Five randomly selected subjects are given alcohol to produce legal drunkenness and then are given a simulated driving test (scored from a top score of 10 to a bottom score of 0). Five different randomly selected subjects are given marijuana and then the same driving test. Finally, a control group of five subjects is tested for driving while sober. The driving test scores and the One-Way ANOVA table for these data are shown below. Test the hypothesis that there is a difference among the means of the three groups at 1% significance level. Alcohol 3 Drugs 2 Control 8 4 6 7 2 4 8 1 4 3 3 5 6 The following is the summary statistics for the table above generated from an Excel one-way ANOVA analysis: ANOVA ces SS df MS F P-value Between 46.800 2 23.400 13.500 0.000848594 Groups Within 20.800 12 1.733 Groups Total 67.600 14 Based on the Excel output, does there appear to be a…

1. with Suppose we obtain a random sample of size 64 from a population 31 and σ = 4. Using the Central Limit Theorem, (a) Find the probability that the sample mean falls in the interval (29.5, 31.5). (b) Find the 15th and 70th percentiles for the sampling distribution of ; that is, find P15 and p70 such that P(P15) 0.15 and P(≤P70) ≈ 0.70.

2. Use the t-table as needed and the following information to solve the following problems. Based on a sample of size n = 21 drawn from some(approximately) normally distributed population with unknown population mean μ and unknown population variance o², we have 82.28 and s = 7.2 (a) Based on the given data information, find the 95% confidence in- terval for the population mean. Round your answer to two decimal places. (b) Based on the confidence interval got in (a), do you believe that the mean length for the population of all screws is 85? Why?

Do not answer: The average income of employees in a company is $50,000 with a standard deviation of $5,000. If a sample of 100 employees is selected, what is the probability that the sample mean income will be between $49,000 and $51,000?

please skip this question: A researcher wants to model the relationship between hours of study (X) and exam scores (Y). The following data was collected: Hours of Study (X): 1, 2, 3, 4, 5 Exam Scores (Y): 55, 60, 65, 70, 75Calculate the linear regression equation and interpret the slope and intercept.

A factory produces light bulbs, 95% of which pass quality control, while 5% are defective. If 10 bulbs are randomly selected, what is the probability that exactly 2 of them are defective? Use the binomial distribution.