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Finding the Fourth Proportional to 638.03, 880.34 and 497.90

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Solution

The fourth proportional to 638.03, 880.34 and 497.90 is: 686.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.03 : 880.34 = 497.90 : x
  2. Step 2: Convert to fraction form
    638.03/880.34 = 497.90/x
  3. Step 3: Cross multiply
    638.03x = 880.34 × 497.90
  4. Step 4: Simplify right side
    638.03x = 438,318.13
  5. Step 5: Solve for x
    x = 438,318.13/638.03
  6. Step 6: Final answer
    x = 686.99

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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.