What number must be added to 15, -6, and 12 to have a mean of 5?

Describe in detail how you would construct a 95% confidence interval for a set of 30 data points whose mean is 20 and population standard deviation is 3. be sure to show that you know the formula and how to plug into it. also, clearly state the margin of error.

Gregory draws a scale drawing of his room. the scale that he uses is 1 cm : 4 ft. on his drawing, the room is 3 centimeters long. which equation can be used to find the actual length of gregory's room?

Suppose your school costs for this term were $4900 and financial aid covered 3/4 of that amount. how much did financial aid cover? and how much do you still have to pay?