The SAT questions students miss most, from Dolphin practice data

The 10 most-missed of Dolphin’s 162 sample SAT questions

Each row is one question from Dolphin’s SAT practice set. “Missed on first try” is the share of students whose first answer to that question was wrong. Across the 162 questions compared, the median was 34%.

Rank	Skill the question tests	SAT domain	Students who tried it	Missed on first try
1	Linear functions	Algebra	645	81%
2	Percent change	Problem-Solving and Data Analysis	1,060	81%
3	Geometry: angles and triangles	Geometry and Trigonometry	2,090	76%
4	Circle equations	Geometry and Trigonometry	2,042	73%
5	Percentages	Problem-Solving and Data Analysis	2,255	72%
6	Linear equations	Algebra	650	66%
7	Sentence boundaries	Standard English Conventions	928	66%
8	Boundaries between clauses	Standard English Conventions	1,462	64%
9	Text structure	Craft and Structure	1,406	64%
10	Inferences	Information and Ideas	505	63%

Six of the ten are Math questions, and two of the top five test percents. Each skill links to a practice page with worked examples.

Which SAT domains students miss most

Dolphin’s full-length SAT practice tests report results for the eight College Board domains. Across 600 completed practice tests with no more than 5 questions left blank, here is the share of questions students missed in each domain. Blank answers count as missed.

SAT domain	Section	Questions	Missed
Problem-Solving and Data Analysis	Math	4,955	43.8%
Geometry and Trigonometry	Math	5,420	40.4%
Advanced Math	Math	6,552	39.5%
Expression of Ideas	Reading and Writing	6,285	38.1%
Information and Ideas	Reading and Writing	11,821	36.3%
Craft and Structure	Reading and Writing	9,310	36.1%
Standard English Conventions	Reading and Writing	4,984	34.6%
Algebra	Math	9,446	32.7%

Dolphin’s practice tests do not split questions across the domains in exactly the real SAT’s proportions, so read this table for miss rates, not question counts. On the real test, College Board says Problem-Solving and Data Analysis and Geometry and Trigonometry each make up only about 5 to 7 Math questions, while Algebra and Advanced Math each make up about 13 to 15.

Why these questions trip students up

The most-missed questions cluster around a few habits. Each fix below is short enough to use on test day.

Percents and percent change

• Dividing by the new value. Percent change uses the original value. If a price rises from $50 to $60, the change is 10, and 10 / 50 = 20%. Dividing by 60 gives about 16.7%, a common wrong choice.
• Undoing a percent with the opposite percent. If a price is $75 after a 25% increase, the original is 75 / 1.25 = $60. Taking 25% off $75 gives $56.25, which is wrong.
• Fix: write the multiplier first. An increase of p percent is 1 + p/100, and a decrease is 1 - p/100.

Linear functions and linear equations

• Mixing up slope and starting value. In y = mx + b, m is the rate of change and b is the value when x = 0.
• Answering for the wrong quantity. If 3x + 5 = 20 and the question asks for 6x, the answer is 30, not 5.
• Fix: before solving, underline exactly what the question asks for, and check the units on both axes of any graph.

Geometry and circle equations

• Forgetting angle totals. Angles in a triangle add to 180 degrees, angles on a straight line add to 180 degrees, and a full circle is 360 degrees.
• Reading the circle equation too fast. In (x - 3)^2 + (y + 2)^2 = 49, the center is (3, -2), not (-3, 2), and the radius is 7, not 49.
• Fix: label every given angle or length on the figure, and check whether a question gives the radius or the diameter.

Sentence boundaries

• Joining two complete sentences with only a comma. “The data were clear, the team published the results” needs a period, a semicolon, or a comma plus a word like “so.”
• Treating a dependent clause as a sentence. Words like because, although and when usually start a clause that cannot stand alone.
• Fix: before choosing punctuation, decide whether each side could stand on its own as a sentence.

Text structure and inferences

• Summarizing instead of naming a function. A structure question asks what a sentence does, such as giving an example or raising a contrast, not just what it says.
• Choosing a conclusion stronger than the evidence. Answers with words like always, proves or all often go beyond what the passage supports.
• Fix: point to the exact words in the passage that support your answer. If you cannot, choose again.

What this data can and cannot tell you

• It shows where many students slip, not where you will. Dolphin students are not a random sample of SAT test takers.
• First tries include guesses. A high miss rate can mean a hard skill, a tricky question, or a question students rushed.
• It is practice data. None of these results come from a scored SAT. Dolphin practice test results are estimates, and College Board’s Bluebook tests are the best check of where you stand.

The most useful list is your own. Keep a log of every question you miss, sort the misses by skill, and practice the two or three skills that cost the most points. Dolphin’s free iPhone and Android apps adapt practice to the topics you miss most.

How we calculated this

• Question results: every answer recorded in Dolphin’s apps and website from June 22 to October 31, 2026 (data pulled October 31), for a fixed set of 163 SAT practice questions that Dolphin’s team chose to represent its SAT skills. For each student and question, only the first answer counts. Questions answered by fewer than 300 students were left out, which removed one question. The 162 remaining questions had 238,654 first answers.
• Domain results: 600 completed full-length Dolphin SAT practice tests taken by 471 students from June 5 to October 31, 2026. Only tests with at least 90 questions and no more than 5 left blank were counted.
• Privacy: this page uses totals only. No student can be identified from it.

Frequently asked questions

What SAT Math topic do students miss most?

In Dolphin practice data, percents stood out. Two of the five most-missed questions tested percent change and percentages, and Problem-Solving and Data Analysis, the domain that includes percents, had the highest miss rate in Dolphin full-length practice tests: 43.8% of those questions were missed.

Are these official SAT questions?

No. The question results come from practice questions in Dolphin's question bank, and the domain results come from Dolphin's full-length practice tests. Neither comes from a scored SAT. Use Bluebook for official College Board practice tests.

Should I study only the most-missed skills?

No. A skill many students miss may not be one you miss. Start with your own wrong answers in Bluebook and in practice, then use this list to check skills you have not practiced recently.