What is the value of the expression 3 + 4 × 2?
- 11 Correct answer.
- 24
- 14
- 9
Explanation
Multiplication is performed before addition, so 4 × 2 = 8 and then 3 + 8 = 11. Evaluating strictly left to right would give a different, incorrect result.
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The probability of a red ball first is 3/8, and then 2/7 for the second since one red ball is removed. Multiplying gives (3/8)(2/7) = 6/56 = 3/28.
Here a = 2 and d = 3, so the 20th term is 2 + 19 × 3 = 59. The sum is (20/2)(2 + 59) = 10 × 61 = 610.
A square linear system fails to have a unique solution when the coefficient determinant vanishes. The determinant is k(1) − 2(4) = k − 8, which is zero when k = 8.
Combine the fractions over the common denominator 6: 6/6 + 3/6 + 2/6 = 11/6. This also equals the sum of pairwise products divided by the product of roots, 11/6.
Factor the numerator as (x − 2)(x + 2), which cancels the denominator for x ≠ 2. The expression then equals x + 2, whose value at x = 2 is 4.
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Dividing by a fraction is the same as multiplying by its reciprocal, so (2/3) ÷ (4/9) = (2/3) × (9/4). Simplifying gives 18/12 = 3/2.
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The word has 5 letters with L repeated twice and E repeated twice. The number of distinct arrangements is 5! / (2! × 2!) = 120 / 4 = 30.
Using standard values, cos 0° = 1, tan 45° = 1, and sin 90° = 1. Substituting gives 1 + 1 − 1 = 1.
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Perpendicular forces combine by the Pythagorean rule, since the resultant is the vector sum. The magnitude is the square root of (3² + 4²) = 25, which gives 5 N.
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