I run out of time on SAT maths. How do I decide which questions to skip?

Decide before you read the whole question, not after you have spent two minutes on it. The skill is recognising a time sink in the first few seconds, and it is trainable.

The two-pass method

Work the section in two passes rather than one.

First pass: answer everything you can do confidently and quickly. If a question does not resolve into a clear method within about fifteen seconds, mark it and move on immediately. Do not start working it.

Second pass: return to the marked ones with whatever time remains, hardest last.

The reason this beats working straight through is that every question is worth the same. A question you can do in forty seconds is worth exactly as much as one that takes four minutes. Spending the four minutes while three easy questions sit unread at the end of the section is the single most expensive habit in the test.

What a time sink looks like

Learn to recognise these in the first glance:

Heavy setup. A long word problem that needs two or three equations built before any solving starts. Often doable, rarely quick.

Nested unknowns. A question where finding what is asked requires finding two other things first.

Geometry with no diagram. You have to draw it, and your drawing has to be roughly accurate before the relationships become visible.

Anything where your first reaction is "there must be a trick". There usually is, and hunting for it is what consumes the time.

Mark and move. You lose nothing by coming back.

Use the answer choices

On a multiple-choice question, the options are information and most students ignore them.

Work backwards. If the question asks for a value and the options are five numbers, substituting them into the condition is often faster than solving. Start with the middle value — if it is too large you have eliminated three options at once.

Pick numbers. For a question with variables in the answers, choose a simple value, work it through, and see which expression matches. Avoid 0 and 1, which often make several options agree.

Estimate. If the options are far apart, an approximation decides it without exact arithmetic.

None of these are available on a question you have to produce the answer for, so save them for where they apply.

The habit worth building

Practise sections under a real time limit from the beginning, not after you have learned the content. Accuracy without speed is only half the skill, and the two interfere with each other in ways that are invisible when you practise untimed.

Afterwards, review not just the questions you got wrong but the ones that took too long and you got right. Those are the ones that cost you the questions at the end, and they never appear on a list of errors.