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Finding the Fourth Proportional to 638.61, 881.26 and 358.86

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Solution

The fourth proportional to 638.61, 881.26 and 358.86 is: 495.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.61 : 881.26 = 358.86 : x
  2. Step 2: Convert to fraction form
    638.61/881.26 = 358.86/x
  3. Step 3: Cross multiply
    638.61x = 881.26 × 358.86
  4. Step 4: Simplify right side
    638.61x = 316,248.96
  5. Step 5: Solve for x
    x = 316,248.96/638.61
  6. Step 6: Final answer
    x = 495.21

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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.