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Finding the Fourth Proportional to 638.15, 880.62 and 358.39

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Solution

The fourth proportional to 638.15, 880.62 and 358.39 is: 494.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.15 : 880.62 = 358.39 : x
  2. Step 2: Convert to fraction form
    638.15/880.62 = 358.39/x
  3. Step 3: Cross multiply
    638.15x = 880.62 × 358.39
  4. Step 4: Simplify right side
    638.15x = 315,603.61
  5. Step 5: Solve for x
    x = 315,603.61/638.15
  6. Step 6: Final answer
    x = 494.56

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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.