A statistical question is one that can be answered by collecting data and where there will be variability in that data. This is different from a question that anticipates a deterministic answer. For example, "How many minutes do 6th grade students typically spend on homework each week?" is a statistical question.
First we need to isolate the variable so we add 15 to both sides which is w/4=43 then we need to multiply by 4 to both sides so its 4w=172 then divide by 4 which is 43 so the answer is w=43