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Finding the Fourth Proportional to 638.31, 880.77 and 358.55

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Solution

The fourth proportional to 638.31, 880.77 and 358.55 is: 494.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.31 : 880.77 = 358.55 : x
  2. Step 2: Convert to fraction form
    638.31/880.77 = 358.55/x
  3. Step 3: Cross multiply
    638.31x = 880.77 × 358.55
  4. Step 4: Simplify right side
    638.31x = 315,800.08
  5. Step 5: Solve for x
    x = 315,800.08/638.31
  6. Step 6: Final answer
    x = 494.74

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.