The Critical Reading, formerly verbal, section of the SAT is made up of three scored sections, two 25-minute sections and one 20-minute section, with varying types of questions, including sentence completions and questions about short and long reading passages. Critical Reading sections normally begin with 5 to 8 sentence completion questions; the remainder of the questions are focused on the reading passages. Sentence completions generally test the student's vocabulary and understanding of sentence structure and organization by requiring the student to select one or two words that best complete a given sentence. The bulk of the Critical Reading questions is made up of questions regarding reading passages, in which students read short excerpts on social sciences, humanities, physical sciences, or personal narratives and answer questions based on the passage. Certain sections contain passages asking the student to compare two related passages; generally, these consist of short reading passages as well as longer passages. Since this is a timed test, the number of questions about each passage is proportional to the length of the passage.
Most of the questions on the SAT are multiple choice; all multiple-choice questions have five answer choices, one of which is correct. The questions of each section of the same type are generally ordered by difficulty. However, an important exception exists: Questions that follow the long and short reading passages are organized chronologically, rather than by difficulty. Ten of the questions in one of the math sub-sections are not multiple choice. They instead require the test taker to bubble in a number in a four-column grid.
The questions are weighted equally. For each correct answer, one raw point is added. For each incorrect answer one-fourth of a point is deducted. No points are deducted for incorrect math grid-in questions. This ensures that a student's mathematically expected gain from guessing is zero. The final score is derived from the raw score; the precise conversion chart varies between test administrations.
The SAT therefore recommends only making educated guesses, that is, when the test taker can eliminate at least one answer he or she thinks is wrong. Without eliminating any answers one's probability of answering correctly is 20%. Eliminating one wrong answer increases this probability to 25%; two, a 33.3% probability; three, a 50% probability of choosing the correct answer and thus earning the full point for the question.
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