what is the margin of error for a sample statistic for a population with a standard deviation of 6.75

What properties allow transformation to be used as a problem solving tool

Can you me find the missing length. i attached an image.

One number is 4 less than 3 times a second number. if 3 more than two times the first number is decreased by 2 times the second number, the result is 11. use the substitution method. what is the first number?