A friend has an annoying habit of ordering expensive meals when we go out to eat. I order modestly. When it’s time to pay, she suggests splitting the bill in half, or she asks me to contribute more to the tip than I should. I don’t want to look petty or cheap, but this drives me crazy. I also don’t want to burden the waiter by asking for separate checks. What to do? —DINER

Burden the waiter! If you are aggravated by paying a few bucks more in tip than you owe, I can’t imagine a solution here for splitting taxes and tips that doesn’t involve complex math. In my experience, waiters don’t mind separate checks for small parties if you ask for them up front. Worse than hard math, I suspect the alternatives to this approach will harden your instinct that your friend is ordering lavishly to take advantage of you—which is probably not the case. I respect your desire (or perhaps your need) for frugality when dining out, but you can accomplish that with a simple request: “May we have separate checks, please?”

—Adapted from “Social Q’s” in The New York Times Magazine