Solve x/3 + x/4 = 14.
Answer and explanation
Correct answer: B. x = 24
- Step 1: Use the common denominator 12: 4x/12 + 3x/12 = 7x/12. Step 2. Then 7x/12 = 14, so 7x = 168. Step 3. x = 24. Answer: x = 24. Why not the others: x = 49: This adds the fractions as 2x/7, adding numerators and denominators, then solves 2x/7 = 14. x = 12: This gives the common denominator rather than the solution. x = 98: This multiplies 14 by 7 instead of by 12/7.
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