Module 8
解答形式の罠 （Kaitō Keishiki no Wana）
帰国子女・インターナショナルスクール生のための、デジタルSAT 数学の無料教材。独学で進められます。
The SAT routinely asks for something one step past the variable you solved for: not x but 4x, not a but a + 3, not the length but the area. Your correct value for x is sitting there among the choices, waiting.
The habit that fixes this permanently. Before you start, underline the final few words of the question — "what is the value of 4x". When you reach an answer, read those words again before you select. This costs about three seconds and is the highest-return habit in SAT Math.
これは日本語の文法のせいではありません。原因は読む速度です。第二言語で解いているあいだは、注意の大半が問題設定の読み取りに取られます。そして計算が終わるころには、最後の what is the value of … の正確な言い回しが記憶から薄れています。必要なのは語学力ではなく手順です。解き始める前に、問われている量に線を引いておきます。そうすれば、あとで読み直すのに手間はかかりません。
If 2x − 5 = 11, what is the value of 4x?
Correct Answer: C
Explanation: 2x = 16 → x = 8 → 4x = 32.
2x — stopping one step earlier still.8x, from doubling once too often.Rated Easy as algebra. Every distractor is a genuine intermediate value from the correct solution path, which is exactly why this format is so effective against fast workers.
If x + y = 7, what is the value of 3x + 3y?
Correct Answer: C
Explanation: 3x + 3y = 3(x + y) = 3 × 7 = 21. You never need x and y individually.
x + y, copied without applying the factor of 3.7 + 3 — the 3 was added rather than multiplied.Rated Hard. Choice D is supported by a correct observation that leads to the wrong conclusion — the most dangerous kind of distractor.
If 5a = 20, what is the value of a + 3?
Correct Answer: B
Explanation: a = 4, so a + 3 = 7.
20 + 3 — the 3 was added before dividing by 5.Rated Easy, included to make the pattern unmistakable: on the SAT, "what is the value of…" is very often not the variable in the equation.