What's a useful tip for Problem Solving and Data Analysis SAT Math questions?
Always draw, diagram, and document. Most of these type of questions are based on real world examples, and there sometimes isn't a straightforward formula for the question at hand. Creating a visual for the question helps you to pin it to a real situation.
What's a useful formatting tip in Excel?
If you have a cell that you like the format of (say, the font and cell color), you can use the Format Painter to just copy that to another cell. Format Painter is the command ribbon at the top, under home, to the left.
What are confidence intervals? What's the point?
Confidence intervals are generally easier explained using an example: Let's say I'm your manager, and I asked you to estimate the average weight of everyone in New York City. It's pretty much impossible to ask every NYC resident and get an accurate answer. The next best thing to do is to ask, say, 20 people in New York City what their weight is. Let's say that you do this and the average weight of these 20 people is 160 lbs. You can now tell me, "Hey, my guess is 160 lbs." That answer's okay, but doesn't tell me anything how you only asked 20 people, so you're not married to 160 lbs. A better answer would be a range, "I think the average weight of people in NYC is 150-170 lbs." That's essentially the idea of a confidence interval.