Is this the exact question. Are they saying WITHOUT a repair contract, the annual cost to maintain the printer (and I'm assuming the computer as well) would be $120.00 (with a standard deviation of $30)?
Is this the entirety of the question? Do you know how to find the EXPECTED VALUE of something?
No. Mean and standard deviation can not be added like this. What class is this in, so we can get some background on what they might be expecting of you (calculation wise).Would I just find the mean cost and standard deviation for the computer and just add the two. So for computer Mean = 105 Dev= 13.675 so add (120+105) + (13.675+30)? thus equals = 268.675 for total cost?