In sampling without replacement from a population of 900, it's found that the standard error of the mean,σ_x , is only two-thirds as large as it would have been if the population were infinite in size. What's the approximate sample size? 200 600 400 500

A professor wants to know whether or not there is a difference in comprehension of a lab assignment among students depending on if the instructions are given all in text, or if they are given primarily with visual illustrations. She randomly divides her class into two groups of 15, gives one group instructions in text and the second group instructions with visual illustrations. The following data summarizes the scores the students received on a test given after the lab. Let the populations be normally distributed with a population standard deviation of 5.32 points for both the text and visual illustrations. Text (Group 1) Visual Illustrations (Group 2) 57.3 59 45.3 57.6 87.1 72.9 61.2 83.2 43.1 64 87.3 76.7 75.2 78.2 88.2 64.4 67.5 89 86.2 72.9 67.2 88.2 54.4 43.8 93 97.1 89.2 95.1 52 84.1 Is there evidence to suggest that a difference exists in the comprehension of the lab based on the…

An experiment consists of casting a six–sided die (numbered 1 through 6) and observing the number that appears uppermost. Find the mean and variance of this experiment. (Round your variance to two decimal places.)

A developmental psychologist is interested in studying how long babies gaze at a photograph of a human face. To test this question, she shows a picture to a sample of six babies and records the length of their gaze in seconds. The data are as follows: 12, 17, 18, 20, 20, 29. Calculate the mean, median, mode, range, variance and standard deviation for the sample.