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Digital SAT practice
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A quick run every day, an explanation for every question, and full-length tests on official timing.
Free, no card. You also get 36 practice questions a day: 12 easy, 12 medium and 12 hard.
The DailySTEP 1
- Three hearts. A miss costs one.
- Streaks pay. ×2 from three in a row, ×3 from six.
- Your longest streak. Beat it tomorrow.
Full-length tests
The real test, rehearsed.
98 questions across four modules, in the digital SAT’s order and on its timing, with a highlighter, a question map and a timer you can see.
How it works
One run a day. One skill at a time.
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Play the Daily.
A quick run with three hearts. String right answers together and the questions get harder and the points multiply.
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Miss one, learn why.
Every question is tagged by domain and skill, and every answer comes with an explanation.
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Drill that skill.
Practice any single skill at any difficulty, or just the questions you got wrong.
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Beat your best.
Come back tomorrow and climb. Progress shows your accuracy and your strongest skills.
Built around the real SAT blueprint.
Every question is tagged by section, domain, skill and difficulty, so you can practice exactly what you need. Full tests run like test day: two Reading & Writing modules, a break, then two Math modules.
Free daily practice
12 easy, 12 medium and 12 hard questions free every day, each with a full explanation. Filter by section, domain, skill and difficulty. Resets at midnight.
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Take any test on official timing, extended 1.5× time, or untimed to focus purely on accuracy.
Adaptive full-length tests
Four modules in official order. The second module of each section adapts to how you did on the first.
Vocabulary
1,023 essential SAT words. Browse the list, flip flashcards, or quiz yourself.
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Accuracy across daily practice and full tests, your strongest skills, and the ones that need the most help.
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PEAK Survivor, Hole and Peak Defense: three games powered by SAT practice questions.
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MathProblem-Solving and Data AnalysisHard
A store raises the price of a jacket by 20%. Later, it lowers the new price by 20%. The final price is what percent of the original price?
A80%
B96%Correct
C100%The trap
D104%
Check with $100: $100→then$120→then$96
Turn each change into a multiplier.
Up 20% means × 1.20. Down 20% means × 0.80.
Apply them in order.
1.20 × 0.80 = 0.96
Read the answer.
The final price is 96% of the original. That’s B.
Why not 100%?
The 20% cut is taken from the higher price, so it removes more than the 20% increase added.
Test day
What test day looks like.
Every Peakscor full test follows this order. In the standard tests, the second module of each section adapts to how you did on the first.
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Reading & Writing · Module 1
27 questions32 min
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Reading & Writing · Module 2
27 questions32 min
Adapts to how you did on Module 1. -
Break
10 min
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Math · Module 1
22 questions35 min
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Math · Module 2
22 questions35 min
Adapts to how you did on Module 1.
98 questions · 2 hr 14 min of testing, plus the break
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Questions, answered.
The Daily, plus 36 practice questions every day: 12 easy, 12 medium and 12 hard, each with a full explanation. Full-length Test A, Challenge Test 1 and all 1,023 vocabulary words are free too. No card needed.
Pro is $20 a month or $200 a year: unlimited practice with no daily limit, plus every full-length test and Challenge test. Peak is $29 a month or $280 a year: everything in Pro, plus the full Learn course and Peak Plan. Cancel anytime from your account.
98 questions across four modules, in the digital SAT’s order: Reading & Writing Module 1 and Module 2 (27 questions each), a 10-minute break, then Math Module 1 and Module 2 (22 questions each). On official timing that’s 2 hr 14 min of testing. You get estimated section scores and a total at the end.
Yes. In the standard full-length tests, Module 2 of each section is the harder version if you get 60% or more of Module 1 right, and the easier version if you don’t. Challenge tests use the hardest material throughout.
Official timing, extended 1.5× time, or untimed, on every test, including the free ones. Extended time allows 48 minutes for each Reading & Writing module and about 52 for each Math module. Untimed removes the clock so you can focus on accuracy.
A quick run with three hearts. Each right answer builds your streak: the questions get harder as it grows, and your points multiply (×2 from three in a row, ×3 from six). A miss costs a heart and drops you back to easy. Best is your longest streak.
Every day at midnight. You get a fresh 12 easy, 12 medium and 12 hard.
No. Peakscor is an independent SAT practice tool, not affiliated with the College Board. Scores shown are estimates.
Your next point starts today.
Free, no card.
One-variable data · Lesson 4
Spread: range, standard deviation and box plots
Spread describes how far apart the values in a data set are. Two data sets can have the same center and very different spreads.
The range is the greatest value minus the least value. It is quick to find, but it uses only the two extreme values, so a single outlier can make it large.
The standard deviation measures how far the values typically are from the mean. The SAT doesn't ask you to compute it; it asks you to compare. When most values sit close to the mean, the standard deviation is small. When many values are far from the mean, it is large. Two data sets with the same range can have different standard deviations, because the standard deviation depends on every value, not just the two extremes.
A box plot shows five numbers: the minimum, the first quartile (Q1), the median, the third quartile (Q3) and the maximum. Q1 is the median of the lower half of the data and Q3 is the median of the upper half, so each of the four sections (lower whisker, two halves of the box, upper whisker) holds about a quarter of the values. The interquartile range (IQR) is Q3 − Q1, the width of the box: the spread of the middle half of the data. An outlier beyond the other values stretches the range but has little or no effect on the IQR.
A longer section of a box plot does not mean more values are in it. It means the values in that quarter are more spread out.
Worked example Easy
Data set X: 48, 49, 50, 51, 52
Data set Y: 30, 40, 50, 60, 70
Which statement correctly compares the standard deviations of the two data sets?
- X has the greater standard deviation, because its values are closer to one another.
- Y has the greater standard deviation, because its values are farther from the mean.Answer
- They are equal, because both data sets have the same mean, 50, and the same median, 50.
- They are equal, because both data sets have exactly 5 values, spaced in equal steps.
How to solve it
- Both data sets have a mean of 50: each is spread evenly around 50.
- In X, every value is within 2 of the mean. In Y, values are as far as 20 from the mean.
- Values farther from the mean make a larger standard deviation, so Y's is greater. No calculation needed.
Why each choice is right or wrong
- A. Incorrect. This has the meaning of standard deviation backward. Values close to one another and to the mean give a small standard deviation, so X's is the smaller one.
- B. Correct. Both means are 50. The values in Y are as far as 20 from the mean, while every value in X is within 2, so Y has the greater standard deviation.
- C. Incorrect. Equal means and medians describe the center, not the spread. Standard deviation measures how far the values sit from the mean, and Y's values sit much farther away.
- D. Incorrect. The number of values and the even spacing don't set the standard deviation; the size of the steps does. X steps by 1 and Y steps by 10, so Y's values are much farther from the mean.
Worked example Medium
The box plot summarizes the heights, in centimeters, of 40 tomato plants in a garden.
Which statement about the heights is true?
- The interquartile range of the heights is 35 centimeters.
- The interquartile range of the heights is 20 centimeters.Answer
- More plants are between 25 and 40 centimeters tall than between 20 and 25 centimeters tall.
- The median height is 27.5 centimeters.
How to solve it
- Read the five numbers: minimum 10, Q1 20, median 25, Q3 40, maximum 45.
- IQR = Q3 − Q1 = centimeters.
- Check the other statements: 35 is the range, ; the median is the line inside the box, 25; and the sections from 20 to 25 and from 25 to 40 each hold about a quarter of the plants, about 10 each, even though one section is longer.
Why each choice is right or wrong
- A. Incorrect. 35 is the range, maximum minus minimum: . The IQR uses the quartiles: .
- B. Correct. The IQR is the width of the box, Q3 − Q1 centimeters.
- C. Incorrect. Each section of a box plot holds about a quarter of the data, about 10 plants here. The section from 25 to 40 is longer only because those heights are more spread out.
- D. Incorrect. 27.5 is halfway between the minimum and maximum, . The median is marked by the line inside the box, at 25.
Trap Confusing range with standard deviation
The range uses only the largest and smallest values. A data set with the bigger range can still have the smaller standard deviation if most of its values sit close to the mean. Look at where all the values are, not just the ends.
Trap Reading a longer section as more data
Every section of a box plot holds about the same number of values. A long whisker or a wide half of the box shows values that are spread out, not more values.
Desmos When Desmos isn’t faster
Comparison questions are faster by eye: look at how far the values sit from the center. If two lists are given and you want to confirm, type stdev([48, 49, 50, 51, 52]) and stdev([30, 40, 50, 60, 70]) and compare the results. Desmos's stdev gives the sample standard deviation; for two lists of the same size it ranks them in the same order as the population version.
When the SAT shows a box plot, read Q1, the median and Q3 from it. Desmos has a quartile function, but for short lists different methods of finding quartiles can give slightly different values.
Practice
Choose a section, then practice a whole domain or drill a single skill.
Full-length tests
Each test mirrors the digital SAT: 98 questions across four modules, 2 hr 14 min on official timing.
A little harder than the real SAT. These tests can run slightly tougher than test day, which makes them good practice: if you can handle these, the real one should feel easier. No question appears in more than one test, Challenge Tests included.
Challenge Tests Hardest of the hardest
Same 98-question format, but every question is drawn from the toughest SAT material: Challenging-tier math throughout and the hardest reading.
Vocab
Study the classic SAT vocabulary list. Browse, flip flashcards, or quiz yourself.
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