"find expressions for the mean and standard deviation of y if this variable is determined by the expression y

Two times a number plus three times another number equals 4. three times the first number plus four times the other number is 7. find the numbers

The table shown below gives the approximate enrollment at the university of michigan every fifty years. how many more students were enrolled at the university of michigan in 1950 than in 1900?

(co 3) the soup produced by a company has a salt level that is normally distributed with a mean of 5.4 grams and a standard deviation of 0.3 grams. the company takes readings of every 10th bar off the production line. the reading points are 5.8, 5.9, 4.9, 6.5, 5.0, 4.9, 6.2, 5.1, 5.7, 6.1. is the process in control or out of control and why? it is out of control as two of these data points are more than 2 standard deviations from the mean it is in control as the data points more than 2 standard deviations from the mean are far apart it is out of control as one of these data points is more than 3 standard deviations from the mean it is in control as the values jump above and below the mean