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Finding the Fourth Proportional to 638.15, 880.65 and 358.38

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Solution

The fourth proportional to 638.15, 880.65 and 358.38 is: 494.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.15 : 880.65 = 358.38 : x
  2. Step 2: Convert to fraction form
    638.15/880.65 = 358.38/x
  3. Step 3: Cross multiply
    638.15x = 880.65 × 358.38
  4. Step 4: Simplify right side
    638.15x = 315,607.35
  5. Step 5: Solve for x
    x = 315,607.35/638.15
  6. Step 6: Final answer
    x = 494.57

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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.