Solve for x 2x:25 = 6:(x/3)
Correct answer: B. 15
- A. 18
- B. 15
- C. 12
- D. 5
Explanation
Interpret the proportion as 2x:25 = 6:(x/3), giving 2x/25 = 6/(x/3) = 18/x. Hence 2x² = 450, so x² = 225 and the positive value is x = 15. The likely mistake is option c, 12, from cross-multiplying incorrectly or failing to account for x in the denominator.
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Ratios compare quantities in the same units, while proportions state that two ratios are equal. Problems cover simplification, division in a given ratio, direct and inverse variation, scale, and missing terms, with attention to the difference between a ratio and a fraction representing part of a whole.
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