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Finding the Fourth Proportional to 639.78, 958.83 and 346.56

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Solution

The fourth proportional to 639.78, 958.83 and 346.56 is: 519.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.78 : 958.83 = 346.56 : x
  2. Step 2: Convert to fraction form
    639.78/958.83 = 346.56/x
  3. Step 3: Cross multiply
    639.78x = 958.83 × 346.56
  4. Step 4: Simplify right side
    639.78x = 332,292.12
  5. Step 5: Solve for x
    x = 332,292.12/639.78
  6. Step 6: Final answer
    x = 519.38

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.